Propagation of Selected Annuals and ... - Aggie Horticulture

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Propagation of Selected 

Annuals and Herbaceous 

Perennials Used as 

Ornamentals 

INTRODUCTION 

Herbaceous plants are classified as annuals, biennials, or perennials, 

although the differences among these types may not be obvious. They may 

also be classified as hardy, semi-hardy, or tender. In general, the propagation 

procedures for such plants depend on their categories and the locality 

where they are to be grown. In the following list of plants, seed germination 

data are given for some species, including suggested approximate temperatures 

that should give the most rapid and complete germination (223). 

Temperatures provided are for media temperature and it should be recognized 

that the medium can be several degrees cooler than the air temperature. 

In addition, media temperature can be severely lowered if irrigated 

with cold water, which will slow or retard germination. In addition, many 

seeds from herbaceous plants can show some dormancy (125). The propagation 

methods indicated serve as a guide, but some variation from these 

methods may be necessary with individual cultivars (24, 27). 

Acanthus mollis. Bear’s breeches. Hardy perennial used in containers or 

perennial bed for its bold foliage. Seed germination is at 18 to 21°C 

(65 to 70°F). Seeds may benefit from scarification. Plants are commonly 

multiplied by dormant divisions of the crown. It can also be propagated 

by root cuttings. 

Achillea spp. Yarrow. Hardy perennial used in garden beds or as cut flowers. 

Seed germination is at 18 to 21°C (65 to 70°F) with light. Fast propagation 

is common from summer softwood cuttings that respond to auxin 

(266). Propagation by division is easy and necessary for good garden 

performance (286). A. filipendulina can be micropropagated (109). 

Achimenes spp. (92). Cupid’s Bower. Tender perennial commonly 

used in hanging baskets. Seeds germinated in a warm greenhouse 

[24 to 27°C (75 to 81°F)] are used for propagating this species. 

Plants grow from small, scaly rhizomes, which can be divided 

for propagation. Commercial propagation is from softwood 

cuttings in early spring (322) under mist using bottom heat. 

Leaf cuttings have also been successful (213). 

Aconitum spp. (286). Monkshood. Hardy perennial grown 

in garden beds or as a cut flower. Seeds often show dormancy 

and must be moist-chilled below 5°C (41°F) for 6 weeks before


planting. Considered difficult to propagate by seed, 

and fresh seed may be less dormant. Propagation is 

most often accomplished by division of the tuberous 

roots. Once established they should not be transplanted. 

All parts of the plants are poisonous. Can be 

micropropagated (318). 

Adiantum. See Fern. 

Aegopodium spp. Goutweed. A hardy perennial used 

as a groundcover. Easily propagated by division. 

African Violet. See Saintpaulia ionantha. 

Agapanthus spp. Lily-of-the-Nile. Tender perennial. 

Grown for blue lily-like flowers. Some selections come 

true from seeds. The thick rhizomes can also be divided 

to produce new plants. Plants have been micropropagated 

(156). 

Agastache foeniculum. Anise hyssop. A long-blooming 

hardy perennial. Seeds germinate at 18 to 21°C (65 to 

70°F). Propagated by dormant division of the crown or 

stem cuttings that root easily under mist. 

Agave spp. Many species of succulents, including the 

century plant. Plants are perennial. Seeds should be 

sown in sandy soil when mature at 15°C (59°F). 

Reproduces vegetatively by offsets from base of plant, or 

the production of plantlets on the flower stalk of some 

species; these are removed along with roots and repotted 

in spring. Some species produce bulbils that can be 

used for propagation. Agave are commercially massproduced 

by tissue culture for the distillery market (244). 

Ageratum houstonianum. Ageratum (223). Halfhardy 

annual. Blue and white flowering bedding plants. 

Taller forms are grown as cut flowers. Seed germination 

is at 24 to 29°C (75 to 85°F) and may benefit from 

light. Ageratum may also be propagated by mist propagated 

stem cuttings with bottom heat [21 to 24°C (70 

to 75°F)] (99). 

Aglaonema spp. Chinese Evergreen. An important 

foliage plant that is easily propagated by canes (long 

stems), shoot cuttings, division, or seeds. Canes should 

be treated as delicate leaf cuttings. Rooting is enhanced 

with IBA and bottom heat [24 to 29°C (75 to 80°F)] 

(239). Can also be micropropagated (69). 

Agrostemma githago. Corncockle. Hardy annual used 

in the garden bed or container. Seeds germinate within 

1 week at 20°C (68°F). 

Ajuga spp. Bugle flower. Hardy perennial. Blue or 

pink flowers on a spreading groundcover. Naturally 

layers itself by stolons. Can be propagated by seeds, 

propagation of selected annuals chapter twenty one 841 

cuttings, divisions, or tissue culture. Seeds germinate 

within 2 weeks at 20°C (68°F). Division is the most 

common form of multiplication. Variegated foliage 

types are from division or cuttings (286). 

Alcea rosea. Hollyhock. Half-hardy biennial. Seed germination 

is at 20°C (68°F). Where winters are not too 

severe, sow seeds in summer, transplant in fall for 

bloom the following year. For annual production, sow 

seeds in a warm greenhouse in winter and transplant 

outdoors. 

Alchemilla mollis. Lady’s mantle. Short-lived hardy 

perennial grown for its interesting gray-green hairy 

foliage. Seed germination is at 18 to 21°C (65 to 70°F) 

with light. Plants can also be divided. Plants have been 


Allium spp. (94). Ornamental onions; also onion, 

chives, and garlic. Often propagated by seed that is germinated 

at 18 to 21°C (65 to 70°F). Some ornamental 

species may benefit from chilling stratification for 

2 weeks and germination at a cooler temperature 15°C 

(59°F). Plants grow from bulbs, which produce offsets. 

Clumps can also be divided. Many species produce aerial 

bulbils. Can be micropropagated (331). 

Aloe spp. Succulents of the lily family. Propagated by 

seed in well-drained sandy soil. Germination is at 20 to 

24°C (68 to 75°F). Plants produce offshoots that can 

be detached and rooted. Plants with long stems can be 

made into cuttings, which should be exposed to air for 

a few hours to allow cut surfaces to suberize. Some 

species are commercially micropropagated. Aloe barbadensis 

can be micropropagated from shoot explants 

(206, 221). 

Alstroemeria spp. Parrot lily (92). Half-hardy perennial. 

Grown commercially as a cut flower and pot 

plant. Propagated by division of the fleshy rhizome. 

Rhizomes are also multiplied in tissue culture to produce 

disease-free plants (47, 216). Alstroemeria as pot 

plants are propagated from seed. Fresh seeds are dormant, 

but moistened 1-year-old seeds germinate 

after 4 weeks of 18 to 25°C (65 to 77°F) followed 

by 4 weeks of 7°C (45°F) conditions (173). 

Alyssum. See Aurinia or Lobularia. 

Alyxia olivaeformis. Maile. An important foliage 

plant, native to Hawaii. It is propagated almost exclusively 

by seeds which need to be depulped (295). 

Rooting of single-node maile stem cuttings is improved 

by removing one-half leaf surface area, placing greenhouse-grown 

cuttings in water prior to treatment, and 

propagating in a shady cloth-covered greenhouse.


842 part five propagation of selected plant species 

A five-second quick-dip in 3,000 to 8,000 ppm IBA 

improves rooting (296). 

Amaranthus caudatus. Love-lies-bleeding (223). 

Half-hardy annual. Seed germination is at 21 to 24°C 

(70 to 75°F). Light may increase germination (18). 

Sow in warm greenhouse for later transplanting or sow 

out-of-doors when frost danger is past. 

A. tricolor. Joseph’s coat. Same propagation 

methods as A. caudatus. Sensitive to excess water. 

Amaryllis belladonna. Belladonna lily (92). 

Perennial. Grows from bulbs outdoors in mild areas or 

in pots in cold climates. Propagate by bulb cuttings, 

separation of bulbs, or tissue culture (73, 95). 

Amsonia tabernaemontana. Willow amsonia. Hardy 

perennial. Pale blue flowers above willowlike foliage. 

Propagation is from seed or summer softwood cuttings. 

Seed should be stratified at 2 to 5°C (34 to 40°F) for 4 

to 6 weeks. 

Anaphalis margaritacea. Pearly everlasting. Hardy 

perennial used in garden beds or rock gardens. 

Propagation is by seed or division. Seeds germinate 

within 1 week at 18°C (65°F). 

Anchusa capensis. Bugloss. Hardy annual or biennial. 

Seeds germinate within 1 week at 20 to 22°C (68 to 

72°F) with light. Sow seeds in summer for bloom next 

year or plant in greenhouse in winter for later transplanting 

to garden. 

A. azurea. Perennial. Selected clones best propagated 

by root cuttings or clump division (97). 

Anemone spp. Windflowers. Tender perennials. 

A. coronaria. Poppy enemone (209). Seed germination 

is at 15°C (59°F) and may be sensitive to higher temperatures. 

Plants develop from tubers. There is an export 

market for Anemone tubers (128). 

A. blanda. Greek windflower (92). Hardy perennial 

produced from a tuber. Propagated from seed or by 

division of the tuber into sections. 

A. japonica. Japanese anemone and A. xhybrida. 

Hardy perennial. Since seeds do not come true, cultivars 

are propagated by division or by root cuttings 

(102). Roots are dug in fall and cut into 5-cm (2-in) 

pieces, which are laid in flats or in a cold frame, then 

covered with 2.5 cm (1 in) of soil. Plants can be potted 

after shoots appear. 

Anigozanthus spp. Kangaroo paw (189). This native 

perennial Australian genus is used for cut flower production 

and for containerized plants. Seed supplies are 

often scarce, and germination rates of available seed are 

usually low and variable for many species. Hot-water 

and chemical pretreatment can be used to improve germination. 

Some hybrids are sterile and do not set seed 

at all. Clumps of rhizomes can be divided, but the rate 

of multiplication is low and unreliable. The most effective 

means of commercial propagation is through 

micropropagation (201). 

Angelonia angustifolia. Summer snapdragon. A tender 

perennial commonly grown as an annual bedding 

plant. Can be propagated from seed or more commonly 

shoot tip cuttings. Seed is germinated at 22 to 

24°C (72 to 76°F). Auxin-treated (2,500 ppm IBA) 

cuttings should be rooted under mist with bottom heat 

24°C (75°F) (99). 

Anthemis spp. Golden Marguerite, camomile. Hardy 

perennial. Seed is germinated at 20°C (68°F). Plants 

can be divided or propagated by stem cuttings. 

Anthurium andraeanum. Anthurium. Remove offshoots 

with attached roots from the parent plant or 

root two- or three-leaved terminal cuttings under 

mist. Anthurium can be micropropagated using a vegetative 

bud explant (185). Seed propagation is at 

25°C (77°F) and is a lengthy process requiring 1.5 to 

3 years for flowering, and cultivars do not come true 

from seed (143). 

Antirrhinum majus. Snapdragon. Tender perennial, 

treated as an annual. Seed is germinated with 27°C 

(80°F) days and 24°C (75°F) nights (65). Chilling 

seeds at 5°C (40°F) can improve germination. Light 

seeds for the first 3 days, and then provide dark to allow 

radicle growth, and move back to light when seedlings 

emerge. Softwood cuttings root readily. A. majus is 

tissue cultured (224, 235). 

Aquilegia spp. Columbine. Hardy perennials. Seed is 

germinated at 21 to 24°C (70 to 75°F) in light. A short 

period of stratification for 3 to 4 weeks, moist-chilling at 

5°C (41°F), can improve germination (116), but may 

not be necessary for all species. A. chysantha germinates 

better with alternating day/night temperature cycles of 

25°C (76°F) day and 20°C (68°F) night (89). 

Arabis spp. Rockcress. Hardy perennials. Seed is germinated 

at 18 to 21°C (65 to 70°F) and may respond 

to light (18). Softwood cuttings taken from new 

growth immediately after bloom root readily. Plants 

can be divided in spring or fall. 

Arctotis stoechadifolia. African daisy. Half-hardy 

annual. Seed is germinated at 20°C (68°F). Sow 

indoors for later transplanting.


Arisaema spp. Jack-in-the-pulpit. Perennials developing 

from rhizomes or tubers that are used in woodland 

or rock gardens. Propagated by division of the tuber or 

rhizome. Seeds require 60 to 90 days of stratification 

prior to sowing. 

Armeria spp. Thrift. Hardy evergreen perennials. 

Seeds emerge within 2 weeks at 15 to 21°C (59 to 

70°F). Can also be propagated by clump division in 

spring or fall. 

Artemisia spp. Hardy perennial. A. ludoviciana can be 

used as a foliage plant and is propagated by division or 

stem cuttings. A. schmidtiana (wormwood) is a hardy 

perennial used as a specimen plant and is propagated by 

stem cuttings, rather than by division. 

Arum italicum ‘ Pictum.’ Painted arum. Hardy perennial 

produced from a tuber. Evergreen foliage and 

naked red seed heads are attractive for the perennial 

garden. Propagated by division of the tuber. Seed 

requires stratification. 

Aruncus dioicus (A. sylvester). Goat’s beard. A hardy 

perennial used as a specimen or border plant. Seeds 

benefit from a cold stratification treatment of 5°C 

(40°F) for 4 weeks. Seeds germinate at 16°C (60°F). 

Usually propagated by dormant crown divisions. 

Asarum spp. Ginger. Perennial plants grown in the woodland 

or rock garden. Can be propagated by seed sown in 

the fall (125) or by division of the creeping rhizome. 

Asclepias tuberosa. Butterfly weed. Hardy perennial. 

Seed is germinated at 21 to 24°C (70 to 75°F). Fresh 

seed may need chilling. Vegetative propagation is from 

3-cm-long root cuttings (105) or stem cuttings taken 

before the plants flower. Plants should not be disturbed 

once established. 

A. curassavica. Bloodflower. Tropical perennial. 

Propagated by seed or by rooting softwood cuttings. 

Long taproot makes division difficult. 

Asparagus asparagoides. A. plumosus (fern asparagus), 

A. sprengeri (Sprenger asparagus). Tender perennials. 

Propagated by seeds at 24 to 30°C (75 to 86°F). 

Sow seeds soon after they ripen, since seeds are shortlived 

(27). Cuttings can be made of young side shoots 

taken from old plants in spring; clumps can be divided. 

Asplenium nidus. Bird’s nest fern. See Fern. 

Aster spp. Hardy perennials. Seed is germinated at 18 

to 21°C (65 to 70°F). Cultivars are propagated by lifting 

clumps in fall and dividing into rooted sections, 

discarding the older parts. If stem cuttings are used, the 


stems must be from juvenile material and rooted under 

long days or the resultant plant will be short and 

quickly flower (100). A. frikartii ‘Monch’ has been 

micropropagated commercially. 

Astilbe spp. Astilbe. Hardy perennials. Propagated by 

division in early spring when 2.5 cm (1 in) tall and then 

again following flowering (29). Seed germination is slow 

and produces a mixed progeny. Seed is germinated at 16 

to 21°C (60 to 70°F) in the light (286). 

Astrantia spp. Masterwort. Perennial with unusual 

and attractive flowers. Generally propagated by division. 

Seeds require cold stratification. 

Athrium spp. Painted fern. See Fern. 

Aubrieta deltoidea. Aubrieta. Hardy perennials, 

sometimes treated as annuals. Seed is germinated at 18 

to 21°C (65 to 70°F). Clumps are difficult to divide; 

cuttings may be taken immediately after blooming. 

Aurinia saxatilis (formerly Alyssum saxatile). Goldentuft 

(223). Short-lived hardy perennial grown for its early yellow 

flower display. Seed is germinated at 15 to 21°C (60 

to 70°F). Sow in summer for bloom the following year. 

Germination may be stimulated by light or exposure of 

moist seeds at 15°C (50°F) for 5 days (18). Propagate by 

division or by softwood cuttings in spring. Double forms 

must be propagated by cuttings or division. 

Baptisia spp. False Indigo. Hardy perennial. Baptisia is 

a hard-seeded legume and requires scarification. Seeds 

germinate in 3 weeks at 21°C (70°F). Stem cuttings can 

be rooted and they respond to auxin treatment (266). 

Plants can be divided, and micropropagation is also 

possible (21). 

Begonia spp. Begonia (262, 263). Tropical perennials. 

Seeds, which are very fine and need light, emerge in 2 to 

4 weeks at 22°C (72°F). Best seed germination is at 28°C 

(82°F) for 5 to 7 days followed by 25°C (78°F) until 

seedlings emerge (223). Sow on moist, light medium 

with little or no covering. Begonia species, tuberous 

begonias, and wax begonias are propagated by seed, but 

other types are propagated vegetatively. 

Fibrous-Rooted Begonias. Wax begonias, 

Christmas begonias, and others are propagated by leaf 

cuttings or softwood cuttings taken from young shoots 

in spring or summer. The cytokinin PBA was more 

effective in bud and shoot development from leaf cuttings 

than BA or kinetin (88). 

Rhizomatous Types. Various species and cultivars, 

including Rex begonia plants, are divided or their 

rhizomes are cut into sections. Propagation is usually



by leaf cuttings, but stem cuttings also will root. 

Treatment of leaf cuttings with a cytokinin increases 

the number of plantlets produced per leaf (320). B. 

evansiana produces small tubercles, which are detached 

and planted. 

Tuberous Begonias (130). In addition to seed 

propagation, these can be grown from tuberous stems, 

which are divided into sections, each bearing at least one 

growing point. Leaf, leaf-bud, and short-stem cuttings 

(preferably with a piece of tuberous stem attached) will 

root readily. Can be micropropagated (220, 294). 

Begonia can also be micropropagated using leaf 

petioles (212), petiole explants (243, 264, 265, 320), 

and somatic embryos (229). 

Belamcanda chinensis. Blackberry lily. Summerblooming 

hardy perennial with orange blossoms are 

held above iris-like foliage. Commercially propagated 

by seed that emerge in 3 to 4 weeks at 18°C (65°F). 

Division is also possible while plants are dormant. 

Bellis perennis. English daisy. Hardy perennial often 

treated as an annual or biennial. Seed is germinated at 

21 to 24°C (70 to 75°F) and may respond to light (18). 

Plants may also be multiplied by division. 

Bergenia cordifolia. Hardy perennial with evergreen 

cabbage-like foliage and attractive spring flowers. Can be 

propagated by seed or division. Seeds require chilling stratification 

of 5°C (41°F) for 6 to 8 weeks. Germination is 

within 2 weeks at 21 to 24°C (70 to 75°F) in the light. 

Bergenia is commercially micropropagated (220, 294). 

Bleeding heart. See Dicentra. 

Boltonia spp. Boltonia. Autumn-blooming, hardy 

perennial resembling asters. Seed is germinated at 20°C 

(68°F). Commercially propagated by division while 

plants are dormant. 

Bouvardia ternifolia (153). Scarlet bouvardia. An 

outstanding perennial with scarlet tubular flowers that 

bloom from midsummer to frost in Texas and New 

Mexico. It is propagated by semi-hardwood cuttings 

throughout the growing season. 

Brachycome iberidifolia. Swan River daisy. Annual 

plant grown in hanging baskets or as bedding plants. 

Seeds germinate in 1 week at 21°C (70°F) in light. 

Brassica oleracea. Flowering cabbage or kale. Cool 

season plants grown for fall display of their colorful 

foliage. Seed is germinated at 21°C (70°F). 

Brodiaea spp. (syn. Triteleia) (134). Perennial plants 

grown as cut flowers and produced from a corm. 

Brodiaea is propagated from seed that requires 

stratification for 8 weeks at 3°C (37°F) (133), or from 

cormels. Plants can also be propagated through liquid 

tissue cultures to develop corms (157). 

Bromeliads. About 2,000 species of tropical herbs or 

subshrubs in 45 genera, of which the pineapple 

(Ananas) is the best known. Propagation is mainly by 

seeds or by asexual division of lateral shoots, but micropropagation 

has been used successfully with some 

species (148). Conditions vary for the successful micropropagation 

of Cryptanthus (178), Guzmania, Puya 

(308), Tillandsia, and Vriesea species (205). 

Browallia spp. Amethyst flower (223). Tender, blueflowered 

perennial often treated as an annual. Can be 

used as flowering pot plant indoors in winter. Seed is 

germinated at 24°C (75°F). Softwood cuttings can be 

taken in fall or spring. 

Brunnera macrophylla. Siberian bugloss. Hardy 

perennial with blue forget-me-not flowers that appear 

in the spring followed by large green leaves. Can be 

propagated by seed, division, or root cuttings. 

Commercially micropropagated (240). 

Cactus (70, 234). Large group of many genera, 

species, and some cultivars. Tender to semi-hardy 

perennials. Seed propagation can be used for most 

species, but seeds often germinate slowly. Sow fungicidetreated 

seed in well-drained sterile mixture and water 

sparingly, but do not allow medium to dry out. Pieces 

of stem can be broken off and rooted as cuttings (306), 

or small offsets, which root readily, can be removed. 

Allow offsets to dry for a few days to heal (suberize) cut 

surfaces before rooting. High humidity during rooting 

is unnecessary, but bottom heat is beneficial. Grafting 

is used to provide a decay-resistant stock for certain 

kinds and to produce unusual growth forms. For 

example, the pendulous Zygocactus truncatus is sometimes 

grafted on tall erect stems of Pereskia aculeata. 

Intergeneric grafts are usually successful. A type of cleft 

graft or splice graft is used. The stem of the stock is cut 

off, and a wedge-shaped piece is removed. The scion is 

prepared by removing a thin slice from each side of the 

base, which is fitted into the opening in the stock. The 

scion is held in place with a pin or a thorn. A grafting 

adhesive can be used to adhere scions to stocks of 

transversally cut (tip-grafted) cactus (328). The completed 

graft is held in a warm greenhouse until healed 

(66, 106, 328). The development of cacti shoots by 

micropropagation can be extremely rapid in comparison 

with greenhouse-germinated seedlings (20), and 

where poor branching limits propagation by traditional 

vegetative propagation methods (76, 154, 190).


Caladium hybrids (323). This tropical perennial, 

grown for its strikingly colorful foliage, produces 

tubers. Propagation is by removing the tubers from the 

parent plant at the end of the 4- to 5-month dormancy 

period just before planting. Commercially, tubers are 

cut into 2-cm pieces (chips), each containing at least 2 

buds (“eyes”). Caladiums do best out-of-doors when 

planted after the minimum night temperature is above 

18°C (65°F) or as pot plants maintained with night 

temperatures of 18 to 21°C (65 to 70°F) and day temperatures 

of 24 to 29.5°C (75 to 85°F). Dried caladium 

seed has a short storage life. Seeds require light and 

temperatures between 25 to 30°C (68 to 86°F) (57). 

Can be micropropagated (132). 

Calibrachoa spp. A tender perennial grown as an 

annual bedding plant. Flowers resemble small petunias. 

Commonly propagated from stem cuttings under mist 

and bottom heat 24°C (75°F) (99). 

Calamagrostis acutiflora. Feather reed grass. Hardy 

perennial. Upright grass with attractive flowering 

plumes. Propagation is by division in late spring. 

Calathea spp. Tropical perennials grown as indoor 

foliage plants. Propagation is from division or commercially 

by micropropagation (237). 

Calceolaria spp. Pocketbook plant. Tender perennials 

often grown as annuals and seasonal pot plants. 

Seed is germinated at 21°C (70°F) with light. 

Germination percentages in some species can be low. 

In some cases, propagation is also possible by softwood 

cuttings. 

Calendula officinalis. Pot marigold. Hardy annual 

grown as a bedding plant or cut flower. Plants can 

provide winter bloom in mild climates from seed 

sown in late summer. Seed is germinated at 21°C 

(70°F) in the dark. 

Calla. See Zantedeschia spp. 

Callistephus chinensis. China aster (297). Annual 

grown as a bedding plant or cut flower. Seeds germinate 

at 20°C (68°F). 

Caltha palustris. Marsh marigold. A hardy perennial 

used around water gardens or ponds. Seeds require 

chilling stratification and may benefit from temperatures 

below freezing. Following stratification, sow seeds 

at 18°C (64°F). Propagation is by division. 

Camassia spp. Quamash (92). Hardy perennials produced 

from bulbs. Blue or white spikes emerge in the 

spring above grass-like foliage. Propagation is by offsets 

of the bulb. 


Campanula carpatica. Tussock, Bellflower. Hardy 

perennial. Seed is germinated at 18 to 21°C (65 to 

70°F) and responds to light. Plants can also be divided 

and stem cuttings root easily. 

C. isophylla. Falling stars. Perennial often grown 

as an annual pot plant for indoor use or hanging baskets. 

Seeds are used for hybrid cultivars and germinate 

in 3 weeks at 18 to 21°C (65 to 70°F) with light. 

Cuttings can also be rooted after treatment with 1,000 

ppm IBA from vegetative stock plants kept under short 

days (100). 

C. lactiflora. Bellflower. Hardy perennial. Seeds 

germinate best after 2 to 4 weeks of stratification at 4°C 

(40°F). 

C. Medium. Canterbury bells. Hardy biennial. 

Seeds, which germinate in 2 to 3 weeks at 21°C (70°F), 

are sown in late spring or early summer for bloom the 

following year. 

C. Persicifolia. Peach bells. Hardy perennial. 

Seeds germinate in 2 to 3 weeks at 18 to 21°C (65 to 

70°F) in light. Small offsets can be detached and rooted. 

Many of the named cultivars of Campanula 

species cannot be produced by seed, so division or cuttings 

are used. Cuttings are produced from the rhizomatous 

growth of stock plants, and rooting occurs 

from the etiolated base. Cuttings are placed in peatperlite 

media and given basal heat under glass or in a 

tunnel (England) (269). 

Canna spp. Canna (92). Tender perennial. Cultivars do 

not come true from seed. Seeds, which have hard coats, 

must be scarified before planting. Seeds germinate in 

2 weeks at 21 to 24°C (70 to 75°F). Cultivars are propagated 

by dividing the rhizome, keeping as much stem tissue 

as possible for each growing point. In mild climates, 

rhizomes are divided after the shoots die down in the fall 

or before growth starts in the spring. In cold climates, 

the plants are dug in fall, stored over winter, and divided 

in spring for transplanting outdoors when frost danger is 

over. Plants can be micropropagated (182). 

Capsicum annuum. Christmas or ornamental pepper. 

Tender annual used as a bedding plant or seasonal pot 

plant. Plants are most commonly propagated by seeds 

germinated at 21 to 24°C (70 to 75°F) that emerge 

within 2 weeks. Stem cuttings also root readily. 

Carnation. See Dianthus caryophyllus. 

Catananche caerulea. Cupid’s dart. Hardy perennial. 

Seed is germinated at 18 to 21°C (65 to 70°F). Plants 

may be divided in the fall.



Catharanthus roseus. Vinca (65). Tender annual. 

Vinca is a major bedding plant grown from seed. 

Optimum temperature for germination is 24 to 27°C 

(75 to 78°F) in the dark. Do not keep seeds too moist. 

Vinca is the commercial source of the cancer drugs vincristine 

and vinblastine. 

Celosia argentea and C. spicata. Cockscomb. 

Tender annual. Both plumed and cockscomb (fasciated) 

cultivars are available as bedding plants and cut 

flowers. Seed is germinated at 24°C (75°F). 

Centaurea spp. Tender and hardy perennials. Seeds 

of C. cyanus (cornflower or bachelor button) and 

C. moschata (sweet sultan) emerge in 1 to 2 weeks at 18 

to 21°C (65 to 70°F). 

C. hypoleuca (knapweed), C. macrocephala (Globe 

centaurea), and C. montana are hardy perennials propagated 

by division or seed. Seeds of C. montana are germinated 

at 21 to 24°C (70 to 75°F). C. macrocephala 

has been micropropagated (149). 

Centranthus ruber. Red valerian. Hardy perennial. 

Rose or white-colored flowers are produced throughout 

the summer. Seed is germinated at 15 to 18°C (60 to 

65°F). Stem cuttings are also possible. 

Cephalotus follicularis. Australian pitcher plant. 

Perennial carnivorous plant. Usually propagated from 

IBA-treated leaf or stem cuttings. Easily propagated by 

tissue culture (1). 

Cerastium tomentosum. Snow-in-summer. Hardy 

perennial. Seed is germinated at 20°C (68°F). Easily 

propagated by division in the fall or by softwood cuttings 

in summer. 

Ceratostigma spp. Plumbago. Hardy perennials with 

bright blue flowers on trailing stems. Propagation is 

from softwood cuttings under mist, or division while 

dormant. 

Cheiranthus cheiri (synonym is Erysimum asperum). 

Wallflower. Semi-hardy perennial often treated as a 

biennial. Seeds germinate in 1 week at 16°C (60°F) and 

may respond to light (18). Choice plants may be 

increased by cuttings taken in early summer. 

Chelone spp. (286). Turtlehead. A hardy perennial 

used in wet areas. Propagation is by division or by cuttings. 

Seeds may benefit from 2 to 4 weeks chilling 

stratification. 

Chionodoxa spp. Glory-of-the-snow. Hardy perennial 

bulb. Primarily grown from seed. Ripe seeds are stored 

through the summer at 17°C (63°F) and sown outdoors 

in September to stratify over winter (92). Bulb 

cuttage (see Hyacinthus) and offsets are successful for 

vegetative propagation. 

Chlorophytum comosum. Spider plant. Propagated 

mainly by planting miniature plants developing at ends 

of stolons. Stolon formation is under daylength control; 

short days (12 hours or less daily) promote stolon production 

(131). It can also be propagated by division. 

Chrysanthemum. See Dendranthema. 

Chrysogonum virginianum. Goldenstar. Trailing 

hardy perennial grown for its yellow flowers. 

Propagation is by division in spring or fall. 

Cimicifuga spp. Cohosh. Hardy perennials for the 

border or woodland garden. White flower spikes appear 

in late summer. Propagated by seed or division. Seed is 

germinated at 18°C (65°F) in light. Plants are divided 

in spring. 

Clarkia amoena . (synonym Godetia). Hardy annuals 

grown as cut flowers or pot plants (8). Sow seeds in 

early spring; they germinate at 21°C (70°F). 

Cleome spinosa. Spiderflower. Tender annual. 

Germinate seeds at 21 to 22°C (70 to 72°F) with light. 

Seeds may benefit from brief chilling stratification for 5 

days. Can also be propagated by division. 

Clivia spp. (92). Tropical perennial grown indoors for 

its colorful floral display. Plants can be propagated by 

seeds sown as soon as they are ripe at 21°C (70°F). It is 

more common to divide plants after they finish blooming. 


Cobaea scandens. Cup and saucer vine. Tropical vine 

grown for its large purple flowers. Propagation is from 

seeds that germinate in 1 week at 21°C (70°F). 

Codiaeum variegatum. Croton (247). Tropical perennial. 

Propagated by leafy terminal cuttings in spring or 

summer. Tall “leggy” plants can be propagated by air layering. 

Stem cutting root number (root initiation) was 

unaffected by bottom heat (28°C, 83°F) or increasing 

light intensity; however, root length was increased (314). 

During shipping of cuttings, exposure to light results in 

shorter roots. Unrooted cuttings can be shipped for 5 to 

10 days at 15 to 30°C (59 to 86°F) (313). 

Colchicum autumnale. Autumn crocus, saffron (92). 

Hardy perennial that grows from corms. Seeds are sown 

as soon as they are ripe in the fall but may require chilling 

over winter to germinate. Several years are required 

for plants to reach flowering size. Propagation is from 

offsets of the corm (see Crocus). Can be micropropagated 

(141).


Coleus. See Solenostemon. 

Consilida ambigua. Larkspur. Upright annual plants 

similar to delphinium in bloom. Seeds germinate at 

18°C (65°F) and can self-sow in the garden. 

Convallaria majalis. Lily-of-the-valley. Hardy perennial 

that grows as a rhizome, whose end develops a large 

underground bud, commonly called a “pip.” In fall, the 

plants are dug, and the pip, with attached roots, is 

removed and used as the planting stock. Digging should 

take place in early autumn, with replanting completed 

by late autumn. Single pips may be stored in plastic bags 

in the refrigerator, then planted in late winter for spring 

bloom. Micropropagation has also been successful (309). 

Convolvulus spp. Morning glory. Trailing annuals 

used in hanging baskets or as bedding plants. Seeds 

benefit from hot water scarification and germinate at 

21°C (70°F). 

Cordyline spp. Ti plant (C. terminalis) is easily propagated 

by cuttings and by micropropagation (90, 184). 

Other Cordyline species can be seed-propagated with 

seeds germinating in approximately 4 months with 

30°C (86°F) days and 20°C (68°F) nights. A vegetative 

propagation technique for C. australis, C. kaspar, and 

C. pumillo by division of the underground stems of 

stock plants has been described (238). 

Coreopsis spp. Hardy annuals and perennials. C. grandiflorum 

(tickseed) is a short-lived perennial usually 

grown from seed. Seedlings emerge within 2 weeks 

when sown at 18 to 24°C (65 to 75°F) in light. Growth 

regulator treatment or seed priming (61, 256) can 

improve seed germination. 

C. verticillata can be propagated by cuttings and 

is hardy to zone 3 (81). Perennial clumps can be 

divided in spring or fall. 

Cortaderia selloana. Pampass grass. A half-hardy, 

ornamental grass with large feathery plumes. 

Propagated by clump division. Micropropagation is 

possible from immature flower parts (250). 

Corydalis spp. Garden perennials. Propagated by 

seeds that that should be sown soon after they are ripe 

because they have a short storage life. Sow outdoors or 

provide 6 weeks warm [24°C (75°F)], moist conditions 

followed by 6 to 8 weeks’ chilling [4°C (45°F)] and germination 

at 10°C (50°F). Commonly multiplied from 

dormant crown divisions. 

Cosmos bipinnatus and C. sulphureus. Half-hardy 

annuals grown as cut flowers or garden plants. Seeds 

usually germinate within 1 week at 21°C (70°F). 


Crassula argentea. Jade plant. Succulent perennial 

grown as an indoor pot plant. Can be propagated at 

any time by leaf or stem cuttings. 

Crinum spp. Tender bulbs grown for seasonal flower 

display. Propagation is from offsets of the bulb or bulb 

cuttage techniques such as bulb chipping (see Chapter 15). 

Plants can be micropropagated (267, 301). 

Crocosmia spp. Crocosmia (92). Hardy perennial 

used for cut flowers or border plants. Plants are propagated 

from offsets of the corm. 

Crocus spp. (33). Hardy perennials that grow from 

corms. Seeds germinate as soon as ripe in summer; several 

years are required for plants to flower. When leaves 

die in fall, plants are dug and corms and cormels are 

separated and planted. Tissue culture propagation is 

from corm fragments, isolated buds, or flower parts 

(111, 145). 

Crossandra infundibuliformis. Flame flower. Tender 

perennial grown as a specialty pot plant for indoor use. 

Can be propagated by seeds or cuttings. Seeds emerge 

sporadically over 2 to 3 weeks at 27 to 29°C (80 to 

85°F), but show better germination at alternating 29 to 

21°C (85 to 70°F) day/night regimes (100). Most commercial 

plants are grown from stem cuttings treated 

with 3,000 ppm IBA and rooted under mist or tents 

using bottom heat at 24°C (75°F). Micropropagation is 

possible from axillary shoot explants (129). 

Cucurbita pepo var. ovifera. Ornamental gourds. 

Tender annuals. Seed is germinated at 20° to 30°C (68 

to 86°F). 

Cuphea spp. Mexican heather; bat-faced cuphea. 

Tender perennials grown as bedding plants or in baskets. 

Cuttings root readily without hormone under 

mist with bottom heat at 24°C (75°F). 

Cyclamen spp. (92, 193, 199, 203). Tender and halfhardy 

perennials. Plants grow from a large tuberous 

stem. Cyclamen is propagated best by seeds that germinate 

in 3 to 4 weeks in the dark at temperatures about 

20°C (68°F), no higher than 22°C. Seeds are planted 

from midsummer to midwinter. Germination is best in 

a medium of peat moss to which pulverized limestone 

and mineral nutrients have been added for a pH of 6 to 

6.5 (321). Seedlings under commercial production conditions 

flower after 30 weeks (100). The tuberous stem 

can be divided for the production of a few plants identical 

to the parent. Short shoots of cyclamen with two to 

three leaves are easily rooted in 3 weeks when given a 

10-second dip of 3,000 to 5,000 ppm K-IBA under 

intermittent mist, 21°C (70°F) basal heat, and 1 perlite:1



vermiculite rooting medium (193). Tissue culture is 

used to multiply F 1 hybrids (259). 

Cymbalaria muralis. Kenilworth ivy. Semi-hardy 

perennial. Seed is germinated at 12°C (54°F). Selfseeds 

readily. Softwood cuttings or clump division may 

be used. 

Cynara cardunculus. Cardoon. Large bold perennial 

grown for its thistle-like flowers that appear in late 

summer. Seeds germinate in 3 weeks at 24°C (75°F). 

Plants can also be multiplied by division while dormant 

and by root cuttings. 

Cynoglossom amabile. Chinese forget-me-not. Hardy 

biennial grown as an annual. Seed is germinated at 

20°C (68°F) and may respond to light (18). 

Cypripedium. Lady slipper. See Orchids. 

Dahlia (93). Tender perennials consisting of hundreds 

of cultivars. Commercially propagated by seed, division, 

or stem cuttings. Seed is germinated at 26°C 

(80°F) when planted indoors for later transplanting 

outdoors. Large plants can be dug in the fall before 

frost and stored over winter at 2 to 10°C (30 to 50°F) 

and covered with a material such as soil or vermiculite 

to prevent shriveling. In spring, when new sprouts 

begin to appear, divide the clumps so that each tuberous 

root section has at least one or two buds. Plant outdoors 

when danger of frost is over. Dahlias are often 

commercially propagated by softwood cuttings (93) 

from stems forced in the greenhouse in early spring. 

Tissue culture is used to recover virus-free plants (319). 

Daylily. See Hemerocallis spp. 

Delphinium spp. Hardy perennials, usually propagated 

by seeds, which germinate at 18 to 24C (65 to 

75°F). ‘Giant Pacific’ germinates better with alternating 

26°C (75°F) day and 21°C (70°F) night temperatures. 

There may be some benefit to chilling dry seed at 

3°C (35°F) for 1 week prior to sowing seeds (59, 223). 

Seeds are short-lived and should be used fresh or stored 

in containers at low temperature and reduced moisture. 

Seeds can be sown outdoors in spring or summer to 

produce plants that flower the following year. 

Delphiniums can be propagated by softwood cuttings 

or root cuttings (97). Clumps can be divided in spring 

or fall, but such plants tend to be short-lived. Plants 

can be micropropagated (227). 

Dendranthema xgrandiflorum (formerly 

Chrysanthemum xmorifolium). Garden and greenhouse 

chrysanthemum and Argyranthemum frutescens (formerly 

C. frutescens, Marguerite). Hardy and semi-hardy 

perennials. Shoots 6 to 8 cm (2.5 to 3 in) long are rooted 

as softwood cuttings under mist and with 1,500 ppm 

IBA usually as a talc (99). The best source of new cuttings 

is a mother block (or increase block) grown in an 

isolated area away from the producing area kept under 

long days (43, 101). Such plants are grown in programs 

designed to keep them pathogen- and virus-free and 

true-to-type (27). Disease-indexed stock plants are 

regenerated through micropropagation (53). Unrooted 

cuttings can be held for as long as 30 days at 0.5°C 

(33°F). Chrysanthemum is readily micropropagated by 

shoot-tip and petal-segment explants (26, 171, 253). 

Dianthus caryophyllus (36). Carnation. Tender to 

semi-hardy perennial grown as an annual that has many 

cultivars used in the florist’s trade. Seeds germinate easily 

but are used primarily for breeding. Carnations are 

readily propagated by softwood cuttings (144) with 

mist and auxin treatment. The best source of cuttings is 

a mother (or stock) block isolated from the producing 

area. This block originates from cuttings taken from 

stock plants maintained under a program designed to 

keep them pathogen- and virus-free and true-to-type. 

As with chrysanthemum, carnation stock blocks are 

periodically replenished with meristem-tip culture for 

disease-free plants. Conventional cutting propagation 

then proceeds with these clean stock blocks (see 

Chapter 16). Commercially, rooted cuttings are produced 

by propagation specialists for sale to growers. 

Lateral shoots (“breaks”) that arise after flowering are 

removed and used as cuttings. Cuttings root in 2 to 

4 weeks. Carnations can also be micropropagated on a 

large scale using shoot-tip explants (104). Tissue culture is 

also possible from petal explants (166, 219) and somatic 

embryos have been recovered from leaf explants (327). 

D. barbatus Sweet William. Short-lived perennial 

that is grown as a biennial. Seeds are germinated in 

the summer and seedlings emerge in 1 to 2 weeks at 

21°C (70°F). Seedlings are overwintered in frames and 

flower the following spring. Plants can also be propagated 

by cuttings or division. 

D. chinensis, D. plumarius, and Related 

Species. Garden pinks. Hardy perennials, although some 

kinds are grown as annuals or biennials. Seeds germinate 

readily at 15 to 21°C (60 to 70°F). Softwood cuttings are 

taken in early summer and rooted to produce next year’s 

plants. Layering and division also can be used. 

D. gratinanopolitanus. Cheddar pinks. A popular 

herbaceous perennial. Seeds germinate in 1 to 

2 weeks at 21°C (70°F). The cultivars may be propagated 

by stem cuttings or division.


Diascia spp. Twinspur. Annual plants grown as bedding 

or container plants. Seed germination is in 1 week 

at 21°C (70°F) in light. Shoot tip cuttings root easily 

without auxin or with 2,500 ppm IBA (99). 

Dicentra spp. Bleeding heart. Hardy perennials. Seeds 

are sown in late summer or fall for overwintering at low 

temperatures; alternatively, seeds should be stratified 

for 6 weeks below 5°C (41°F) before planting. Seeds 

will germinate in 3 to 4 weeks at 10 to 13°C (50 to 

55°F). Divide clumps in spring or fall. Stem cuttings 

can be rooted if taken in spring after flowering. Root 

cuttings about 7.5 cm (3 in) long can be taken from 

large roots after flowering. D. exima is commercially 

propagated from seeds or division. D. spectabilis is usually 

propagated by division of the woody rhizome or 

from stem cuttings. It can also be micropropagated. 

Dictamnus albus. Gas plant. Hardy perennial. Seed 

germination is difficult and inconsistent. Stratify seeds 

at 1 to 5°C (34 to 41°F) for 3 to 4 months. Cultivars 

can be propagated from root cuttings. Gas plant is easily 

micropropagated from shoot explants (164). Plants 

should not be disturbed after establishment; thus, division 

is not done. Contact with the leaves of gas plant 

can produce severe dermatitis. 

Dieffenbachia spp. Dumbcane. Tropical perennial. 

Cut stem into 5-cm (2-in) segments, with one or two 

nodes per section, and place horizontally, half exposed 

in sand or other well-drained media. New shoots and 

roots will develop from nodes. If plant gets tall and 

“leggy,” the top may be cut off and rooted as a cutting, 

or the plant may be air layered. Leaves and stem are 

poisonous and may cause rashes on skin. 

Digitalis spp. Foxglove. Hardy biennial or perennial 

plants. Seed is germinated at 15 to 18°C (60 to 65°F) 

in light. Sow seeds outdoors in spring, transplant to a 

nursery row at 9-inch spacing, and then transplant to a 

permanent location in fall. Perennial species is 

increased by clump division. 

Dimorphotheca spp. Cape or African marigold. Halfhardy 

annual with daisy-like flowers. Seeds germinate 

within 1week at 21°C (70°F). 

Dionaea muscipula. Venus flytrap. Carnivorous 

plants, which have unique appearance, unusual mode 

of life, and are in demand by plant collectors. Although 

plants can be grown from seed or division, they are usually 

propagated by tissue culture, from leaves, adventitious 

buds, and peduncle explants (32, 214). 

Dodecatheon maedia. Shooting star. Hardy perennial. 

Unique flowers in white or purple resemble tiny 

darts. Easily divided when plants are dormant (41). 


Seed is sown in autumn to stratify over winter for 

spring emergence. 

Doronicum spp. Leopard’s bane. Hardy perennial 

grown for its early yellow, daisy-like flowers in spring. 

Seed is germinated at 20°C (68°F). Divide plants in 


Dorotheathus bellidiformis (formerly Mesembryanthemum 

criniflorum). Livingstone daisy. Drought-tolerant 

annual grown as a bedding plant. Seedlings emerge 

within 2 weeks at 18°C (65°F) in light. 

Dracaena spp. Variable group of tropical perennial 

foliage plants which are available in bush, cane, tree, and 

stump forms. Seed is germinated at 30°C (86°F). Some 

species are propagated from leaf-bud cuttings that are 

treated with IBA and rooted under intermittent mist. 

D. fragrans, which is an important cane form used for interiorscapes, 

is propagated from cane stem cuttings which 

are cut into 30- to 183-cm (1- to 6-ft) sections waxed on 

the distal (top) end; basal ends are treated with IBA and 

placed in a porous medium without intermittent mist 

under shade (indoors or field-propagated). Branching of 

canes during field propagation is done by cutting 

one-third to one-half way through the cane, which 

results in the development of lateral buds anywhere 

from directly below to 15 cm (6 in) below the cut 

(75). Micropropagation is from stem explants (74, 90, 310). 

Drosera spp. Sundew. Easily grown carnivorous plants 

that produce leaves with conspicuous glandular hairs 

that trap insects. Drosera can be propagated by seed, 

root cuttings (68), or easily from tissue culture (9). 

Non–tuber-forming plants can also be propagated 

from IBA-treated leaf cuttings. 

Dryoptris spp. See Fern. 

Dusty miller. See Senecio spp. or Tanacetum 

ptarmiciflorum. 

Dyssodia tenuiloba. Dahlberg daisy. Tender annual. 

Yellow daisylike flowers on compact edging plants. 

Propagated from seed germinated at 18 to 21°C (65 to 

70°F) in light. Germination can be erratic due to a percentage 

of dormant seeds. 

D. pentacheta. Perennial. A low-growing Texas 

wildflower suitable for xeriscapes. Propagated from 

softwood cuttings treated with IBA under mist or by 


Echeveria. See Succulents. 

Echinacea spp. Purple coneflower. Hardy perennial. 

Purple, orange, yellow, or white flowers typical of the 

sunflower family are attractive as garden plants or as cut



flowers. Seed is germinated at 21 to 25°C (70 to 78°F). 

Germination can be erratic and improved by seed priming 

or chilling stratification at 15°C (59°F) (256, 316, 

317). Garden plants can be divided. Echinacea hybrids 

are commercially micropropagated (71, 139). 

Echinops spp. Globe thistle (223). Hardy perennials. 

Unique metallic blue flowers on thistlelike plants. Seed 

is germinated at 15 to 20°C (60 to 68°F). Plants may 

be divided in spring. Root cuttings, 5- to 7.5-cm (2- to 

3-in) long, may be made in the fall and planted in 

sandy soil in a cold frame. 

Echium spp. Viper’s bugloss. Annual and perennial 

plants grown as bedding or container plants. Plants 

produce large blue spikes of flowers. E candicans (Pride 

of Madeira) is a drought tolerant plant often seen in 

seaside gardens. Propagation is from seed sown at 15 to 

20°C (60 to 68°F). Larger plants can be propagated by 

stem cuttings. 

Epimedium spp. Barrenworts. Hardy perennials. 

Popular ground cover for shady areas. Propagated by division 

in the spring (174). Can be micropropagated (6). 

Epiphyllum spp. Leaf-flowering cactus. Tender perennial. 

Seeds do not germinate well when fresh but will 

after 6 to 12 months’ storage if planted in a warm greenhouse. 

Propagated readily by leaf cuttings (botanically, 

modified stems called phyllocades) or by grafting to 

Optunia. Can be micropropagated (190). See Cactus. 

Epipremnum aureum. Golden pothos. Among the 

most important commercially produced foliage plants. 

Producers cut the long vines into single-node, leaf-bud 

cuttings for propagation. Leaf-bud cutting propagation 

is enhanced with light intensity of about 2,000 ft-c for 

stock plants and basal heat of 28°C (83°F) (312). Stock 

plants should be maintained at four to five nodes (14 to 

15 leaves), with a 3-cm or longer internode section 

below the node, and a fraction of the old aerial root 

retained on the cuttings for most rapid axillary shoot 

development (315). Maintained in the juvenile phase 

by cutting propagation. Mature phase has a much 

larger leaf and flowers. 

Episcia spp. Flame violet. Tropical trailing plants 

grown indoors in hanging baskets. Seed propagation is 

at 24°C (75°F), but plants root easily from stem cuttings 

using mist and bottom heat or plantlets taken 

from ends of the runners. 

Eranthis hyemalis. Winter aconite (92). Hardy perennial 

produced from tubers. Early yellow flowering 

plants popular in the rock garden. Commercially propagated 

from seed (see Chionodoxa). 

Eremurus bungei. Foxtail lily (92). Tender perennial 

produced from a tuberous root. Tall flowering spikes 

are commercially grown as a cut flower. Propagated 

from seed or more commonly by division. Seeds apparently 

have an after-ripening requirement that is satisfied 

by dry storage at 30°C (86°F) for 2 months (329). 

Plants are commercially propagated by division of the 

tuberous roots. 

Erigeron spp. Fleabanes. Hardy perennial. Blue, pink, 

or white daisy-like flowers with yellow centers. Can be 

propagated by seed, division, and stem cuttings. 

Usually commercially propagated by seed that germinates 

at 21 to 24°C (70 to 75°F). 

Eryngium spp. Sea-holly. A diverse species of perennials, 

used as specimen and border plants or as cut flowers. 

Propagation by division is possible, but a long taproot 

makes transplanting difficult. Root cutting 

propagation is the commercial method for species not 

coming true from seed (286). Seeds have a warm-cold 

stratification requirement of 4 weeks at 21°C (70°F), 

followed by 6 weeks of 3°C (38°F) and then a warm 

temperature of 18 to 23°C (65 to 75°F). 

Erythronium spp. Dog’s tooth violet or trout lily 

(92). Hardy woodland perennials with recurved lilylike 

flowers. Plants are used in rock or alpine gardens as 

well as being naturalized. Plants naturally multiply by 

seeds that are spread by ants and by producing new 

plants at the end of slender stolons. Propagation is by 

division. 

Eschscholzia californica. California poppy. Hardy 

annual grown en masse for its flower display. Seed is 

germinated at 21°C (70°F). Seeds can be sown outdoors 

in fall in mild climates or in early spring in colder 

areas. Tends to self-sow. Seedlings may be difficult to 

transplant because of a long taproot. 

Eucomis spp. Pineapple lily (92). Summer-blooming 

perennial bulb. Propagation is by offsets or from seeds. 

Micropropagation by twin scaling offers commercial 

potential (19). 

Euphorbia spp. Euphorbia, spurge. Perennials used as 

border and sometimes specimen plants. Plants are also 

grown for latex production. Propagation is easy by division. 

The thick seeds of E. epithymoides (polychroma) 

take 15 to 20 days to germinate at 18 to 21°C (65 to 

70°F) (286). In vitro techniques have also been developed 

from stem explants (241). 

Eustoma grandiflorum. Lisianthus (223). Annual. 

Grown as a pot plant or cut flower. Seed is germinated at 

22°C (72°F). Plants have been micropropagated (112).


Evolvulus glomeratus. Prostrate plant with blue flowers 

grown as a bedding plant or in hanging baskets. 

Propagation is by stem cuttings using mist. 

Exacum affine. Exacum or Persian violet. A popular 

greenhouse-grown pot plant with fragrant flowers, multiple 

blooms, and good postharvest quality. Can be propagated 

from seed or cuttings. Seeds germinate within 

2 weeks at 21 to 24°C (70 to 75°F). Herbaceous stem 

cuttings root easily with bottom heat [22°C (72°F)]. 

Exacum can also be micropropagated (299). 

xFatshedera lizei. Tree ivy. An intergeneric cross 

between Hedera helix and Fatsia japonica. Propagated 

by auxin-treated stem cuttings using mist and bottom 

heat [24°C (75°F)] or by air layering. 

Felicia spp. Blue daisy. Tender, trailing plants most often 

grown for hanging baskets. Propagation is from stem cuttings 

using mist with bottom heat [21°C (70°F)]. 

Festuca spp. Blue fescue. Hardy perennial grass. A 

clump-forming grass with blue foliage. A warm season 

grass, fescue should be divided in the spring or fall. 

F. ovina glauca comes relatively true from seeds that 

germinate within 1 week at 21°C (70°F). 

Fern (233, 251, 291). Many genera and species. 

Spores are collected from the spore cases on lower sides 

of fronds. Examine these sporangia with a magnifying 

glass to be sure they are ripe but not empty. Place 

fronds with the spores in a manila envelope and dry for 

a week at 21°C (70°F). Screen them to separate spores 

from the chaff. Transfer to a vacuum-tight bottle and 

store in a dry, cool place. Sow spores evenly on top of 

sterilized moist substrate (e.g., two-thirds peat moss, 

one-third perlite in flats), paying particular attention to 

sanitation. Leave 1 inch space on top and cover with a 

pane of glass. Use 18 to 24°C (65 to 75°F) air temperature; 

bottom heat may be helpful. Keep moist, preferably 

using distilled water to avoid salt injury. 

Spores germinate and produce mosslike growth 

composed of many small gametophytic prothalli. 

Fertilization requires free water on the prothallus to 

allow motile male gametes to reach the female archegonium. 

After fertilization occurs, a small leafy sporophyte 

appears in 2 to 3 months on the surface of the 

prothallus. Transplant the developed sporophyte to a 

greenhouse substrate for further growth into the fern 

plant. Procedures have also been developed for in vitro 

fern propagation from spores (177, 188). 

Several vegetative propagation methods are possible. 

Many ferns grow from rhizomes, which can be 

divided. In few species, like sword fern (Nephrolepis 

tuberosa), underground tubers are produced on thin 


stolons and can be used for propagation. Certain other 

ferns (e.g., Cystopteris bulbifera, Polystichum setiferum) 

produce small plantlets (also called bulblets) along the 

leaf surface or leaf tip (Camptosorus rhizophyllum). These 

can be removed and used to produce a new plant (291). 

Cultivars of the sterile (non-propagatable by 

spores) Boston fern group (Nephrolepsis) are now 

largely micropropagated starting with rhizome tips 

(7, 51). This micropropagation technique is also applicable 

to other fern genera, such as Adiantum (maidenhair 

fern), Alsophila (Australian tree fern), Pteris (brake 

fern), Microlepia, Playcerium (staghorn fern), and 

Woodwardia (chain fern). 

Ficus. See Chapter 20 (82, 91). 

Filipendula spp. Queen of the prairie. Hardy perennials 

used in garden beds or naturalized areas. 

Propagation is from dormant divisions or root cuttings. 

Fragaria. Pink Panda. Perennial strawberry plant 

grown for its ornamental pink flowers rather than fruit, 

which it rarely produces. Propagation is from rooted 

plantlets produced on runners. 

Freesia spp. (158). Tender perennials produced from 

a corm. Commercially produced as a cut flower. Seeds 

planted in fall germinate in 4 to 6 weeks and will 

bloom the next spring. A germination temperature of 

about 18.5°C (65°F) is best (127). Plants are commercially 

propagated from cormels that are planted in 

spring and dug in fall. Micropropagation is also used to 

produce corms, as well as disease-free plants (22, 236). 

Fritillaria spp. Checker lily (92). Perennials produced 

from non-tunicate bulbs. Interesting group of 

spring-flowering bulbs of which F. imperialis (crown 

imperial) and F. melaegris are the best known. 

Propagated from offsets, bulb scaling, and bulb cuttage 

(chipping). Micropropagation is also successful (183). 

Fuchsia xhybrida. Fuchsia magellanica hybrids. 

Fuchsias are tender perennials treated as annuals that are 

utilized as hanging baskets, containers, or trained to tree 

form on standards. The most effective way to propagate 

cultivars is by cuttings. Softwood cuttings root easily 

under mist or high humidity with bottom heat at 21°C 

(70°F). Auxin (1,000 ppm IBA) can improve rooting. 

For optimum cutting production it is best to maintain 

stock plants on short day, 10-hour photoperiods (311). 

Gaillardia spp. Blanketflower (223). Annuals and 

hardy perennials. Seed is germinated at 21 to 24°C (70 

to 75°F) in light (18). Perennial kinds can be started 

from root cuttings or may be divided in spring or fall 

but are not long-lived.



Galanthus spp. Snowdrop (92). Hardy perennial produced 

from an annual tunicate bulb. Bulbs are planted 

in the fall for bloom the following spring. Offsets are 

removed when bulbs are dug. G. nivalis and G. elwesii 

are mostly propagated by seed sown as soon as they are 

ripe in the spring. Bulb cuttage (chipping) and twin 

scale micropropagation can also be used (73, 156). 

Galtonia candicans. Summer hyacinth (92). Tender 

bulb with small pendant flowers that are fragrant. 

Propagated by offsets of the bulb. Plants can also be 


Gasteria. See Succulents. 

Gaura lindheimeri. Hardy perennial that produces 

wispy flowers on long stems. Seeds germinate within 

2 weeks at 21°C (70°F). Can also be multiplied by dormant 

division of the crown. 

Gazania spp. (223). Tender perennial often grown as 

an annual. Seed is germinated at 21°C (70°F). Divide 

clumps after 3 or 4 years. 

Gentiana spp. Gentian. Many species, mostly hardy 

perennials, although some are annuals and biennials. Plant 

fresh seed in the fall to overwinter outdoors. Seeds germinate 

in 1 to 4 weeks at 20°C (68°F). However, seeds need 

to be stratified for 3 weeks at 2°C (36°F) or treated with 

300 ppm GA 3 (39). Seedlings are very delicate and should 

not be transplanted until roots are established during the 

first month. Cutting propagation is used for some white 

cultivars, which have poor seed germination. Micropropagated 

liners are now becoming available (147). 

Geranium. See Perargonium. 

Geranium spp. Cranesbill. Hardy perennials. True 

geraniums are popular herbs and perennial garden 

plants. Geraniums can be propagated by seed, division, 

stem, or root cuttings. Seeds germinate in 2 to 4 weeks 

at 21°C (70°F), but fresh seeds may have a hard seed 

coat that requires scarification. Commercial propagation 

is most often by division when plants are dormant 

or from root cuttings taken in the winter. Root cuttings 

are sensitive to rot if overwatered. One approach is to 

allow buds to form on root pieces by holding them in 

“sweat” boxes (polyethylene tents) at near 100 percent 

humidity prior to planting in a potting medium. 

Gerbera jamosonii. Transvaal daisy. Tender perennial. 

Seed is germinated at 20°C (68°F); it is important to use 

fresh seed (64). Alternately, basal shoots from the rhizome 

can be used as cuttings. Commercially, micropropagation 

from shoot tips is used for rapid, large-scale 

multiplication (187, 218). 

Geum spp. Avens. Hardy perennials used in garden 

beds and cut flowers. Common perennial easily propagated 

by seeds. Seed is germinated at 18 to 21°C (65 to 

70°F). Can also be propagated by crown division in 


Gladiolus (78). Tender perennial grown from a corm. 

Popular cut flower. Seed propagation is used for developing 

new cultivars. Seeds are planted in spring either 

indoors for later transplanting or outdoors when danger 

of frost is over (see Chapter 15). Commercial propagation 

is from cormels or division of the corm, leaving 

at least one bud (eye) per piece (202). In vitro techniques 

using buds or liquid-shake culture have 

improved multiplication rates (25, 196, 332). 

Gloriosa spp. Gloriosa lily (92). Tender perennial. 

Vines are produced from tuberous stems. Unique flowers 

with recurved petals are grown as cut flowers or container 

plants. Propagation is from daughter tubers that 

form at the shoot base of the original tuber. 

Micropropagation is possible from tuber explants (114). 

Gloxinia. See Sinningia speciosa. 

Godetia. See Clarkia. 

Gomphrena globosa. Globe amaranth (223). Buttonlike 

white or purple flowers make this a popular cut 

flower and bedding plant. Propagate from seeds that 

emerge in 1 to 2 weeks at 24 to 25°C (75 to 78°F). 

Gunnera spp. Tender perennials producing extremely 

large leaves on creeping rhizomes. Propagation is from 

seed or division. Seeds will germinate in 3 weeks at 

18°C (65°F) with light. Division of the creeping rhizome 

is also possible while plants are dormant. 

Guzmania spp. See Bromeliads. 

Gypsophila spp. (G. elegans). Baby’s breath. Annual. 

Grown as a cut flower. Seed germinates in 2 to 3 weeks 

at 21 to 26°C (70 to 79°F). 

G. paniculata. Hardy perennial. Started by seed 

as above. Plants can be divided in spring and fall. 

Terminal stem cuttings treated with 3,000 ppm IBA 

can be rooted under mist (99). Double-flowered cultivars 

can be difficult to root and can be propagated by 

seeds that yield approximately 60 percent double 

plants. Double-flowering types have also been wedgegrafted 

on seedling G. paniculata (single-flowering) 

roots or crowns. Grafting can be done in summer and 

fall, using outdoor-grown plants for rootstocks and 

placing them in a cold frame for healing of the graft; 

grafting is also done in winter and early spring, using 

greenhouse-grown stock plants. G. paniculata can be 

micropropagated using shoot-tip explants (186).


Haworthia. See Succulents. 

Hedychium spp. Ginger lily. Tropical plants producing 

attractive spikes of flowers from creeping rhizomes. 

Propagation is from division of the rhizome. 

Helenium autumnale. Sneezeweed. Hardy perennial. 

Sunflower-like blooms in unique colors produced 

in late summer in the perennial garden. Seed is 

germinated at 22°C (72°F) with light. Cultivars are 

increased by division. Separate rooted shoots in 

spring, line-out in nursery, then transplant in fall and 

winter. 

Helianthemum nummularium. Sunrose. Hardy 

perennial. Drought-tolerant spring blooming groundcover. 

Seed is germinated at 21 to 24°C (70 to 75°F). 

Cultivars are propagated by softwood cuttings taken 

from young shoots in spring. Transplant to pots and 

place in permanent location the following winter or 

spring. Division of clumps is also possible, but plants 

tend to be short-lived. 

Helianthus annuus. Sunflower. Hardy annual. 

Popular as a cut flower. Seeds germinate within a few 

days at 20 to 30°C (68 to 86°F). Some sunflower cultivars 

show dormancy and benefit from 6 weeks of chilling 

stratification (46). H. decapetalus and other hardy 

perennial species can be propagated by seeds or 

increased by division. 

Helichrysum bracteatum (current name Bracteantha 

bracteata). Strawflower (223). Annual. Popular cut 

flower for drying. Propagated by seeds that emerge in 

1 to 2 weeks at 21 to 24°C (70 to 75°F). 

H. petiolare. (Licorice plant). A trailing plant 

with interesting foliage grown as a companion plant in 

hanging baskets. Propagated from stem cuttings treated 

with 3,000 ppm IBA under mist (99). 

Heliconia spp. (85). These tropical ornamental 

herbaceous perennials are prized for their showy inflorescences. 

Commercially produced as a cut flower, they 

are easily propagated by division of the rhizomes. 

Micropropagated from rhizome buds (222). 

Heliopsis spp. Heliopsis. Hardy perennial with sunflower-like 

flowers. Seed is germinated at 18 to 21°C 

(65 to 70°F). Divide clumps in fall. 

Heliotropium spp. Heliotrope. Tender perennial usually 

grown as an annual. Seed germinates within 

1 week at 21°C (70°F) and may respond to light (18). 

Plants will also root from softwood tip cuttings 

from stock plants grown under short days to remain 

vegetative (99). 


Helleborus spp. Hellebore, Christmas and lenten rose. 

Perennials used as border and woodland gardens. One 

of the earliest plants to bloom in the perennial garden. 

Propagation by seed is very slow. H. lividus has a combinational 

dormancy requirement of warm stratification 

[21°C (70°F)] for 8 to 10 weeks followed by cold 

stratification of 3°C (37°F) for 8 to 10 weeks; seeds still 

may take up to 2 years to germinate. Division is the 

most common method, carried out by carefully separating 

the crown (286). Roots and leaves are poisonous. 

Hellebore can be micropropagated (52). 

Hemerocallis spp. (87). Daylily. Hardy perennial. 

Seed propagation is used only to develop new cultivars 

and requires 6 weeks of stratification; germination 

takes 3 to 7 weeks at 16 to 21°C (60 to 70°F) (286). 

Divide clumps in fall or spring, separating into rooted 

sections, each with about three offshoots. Clones can 

also be micropropagated using flower petals and sepals 

as explants (10, 207). 

Hepatica spp. Hardy perennial used in the rock garden 

or wildflower garden. Propagated by seed or division. 

Seeds have epicotyl dormancy (see Chapter 7) and may 

take 2 years to emerge. Division is in early spring before 

growth begins. Plants can be micropropagated (225). 

Hesperis matronalis. Sweet rocket. A biennial or 

short-lived perennial grown in garden borders or in 

mass display. Seeds germinate in 1 week at 21 to 26°C 

(70 to 75°F). 

Heuchera spp. American alumroot, coralbells. 

Perennials used as border plants for their foliage and 

flowers. Propagated by dormant crown division. Seed is 

germinated at 18°C (65°F) in light. Commercially 

micropropagated from stem explants (279). 

Hibiscus spp. Mallow. Hardy perennials. Large 

saucer-shaped flowers in vibrant colors. Cultivars are 

propagated by division while dormant. Seed is germinated 

at 21 to 26°C (70 to 75°F). 

Hippeastrum spp. Amaryllis (228). Tender bulbous 

perennial. Garden plant and popular indoor flowering 

bulb. Propagated by offsets or micropropagation. Bulb 

offsets will flower the second year. Bulb cuttings (chipping) 

can be made in late summer. Dry membranous seeds are 

borne in dehiscing capsules. Seeds germinate under 

warm conditions at 20 to 30°C (68 to 86°F). Seedlings 

take 2 to 4 years to produce flowers. Micropropagated 

by the twin scaling method (73, 151). 

Hosta spp. Plantain-lily. Herbaceous perennials which 

are used for massed plantings or as specimen plants for 

their foliage and flowers. Propagated by clump division



in spring. One producer removes the apical dominance 

of the crown (terminal) bud, slices (divides) the remaining 

clumps into quarters, places the quarters outdoors 

in trays (England) which are winter-protected, and then 

plants when they begin to shoot. Offset formation has 

also been increased by spraying crowns with cytokinin 

(123). It takes 3 years to produce a flowering plant from 

seed. Micropropagation is being used with new cultivars 

to speed up propagation (208). 

Houttuynia cordata. An aggressive hardy perennial 

plant growing by rhizomes. Tolerates wet conditions 

and is often confined to a shallow pond. Propagation is 

from division or softwood cuttings. 

Hoya spp. Wax flower. Tropical vines grown in indoor 

hanging baskets for its attractive foliage and flowers. 

Propagation is from single node stem cuttings that benefit 

from bottom heat. 

Hummulus lupulus. Hops. Tender perennial vine 

grown as an annual for quick coverage of a support. 

The yellow foliage ‘Aureus’ is most common in gardens. 

Propagated from stem cuttings. 

Hunnemannia fumariifolia. Goldencup. Tender 

perennial often grown as an annual. Seeds germinate in 

2 to 3 weeks at 20°C (68°F). For bloom first year, sow 

seeds early indoors then transplant outdoors when danger 

of freezing is over. 

Hyacinthus spp. Hyacinth (226). Hardy, spring-flowering 

perennial; bulbs are planted in the fall. Removal of 

offset bulbs gives small increase. For commercial propagation, 

new bulbs are obtained by scoring or scooping 

mature bulbs (see Chapter 15). Micropropagation, 

using segments of the bulb, leaf, inflorescence, or stem 

as an explant, is successful (23, 155). Seeds may be 

planted outdoors in fall, but up to 6 years are required 

to produce blooms. 

Hymenocallis spp. Spider lily (92). Tender bulb producing 

large white flowers with extended tepals, suggesting 

the common name. Propagated by offsets from 

the bulb. Plants can also be micropropagated (325). 

Hypericum spp. St. John’s wort. Hardy herbaceous 

and woody perennials grown for their saucer-shaped 

yellow flowers. Also grown as a cut flower. Seed is germinated 

at 21°C (70°F). Plants are also propagated by 

division of the crown or creeping rhizome. Stem 

cuttings will also root easily. 

Hypoestes phyllostachya. Polka dot plant (223). 

Tender annual. Grown as a bedding plant or indoor 

plant because of unique spotted foliage. Propagated 

from seeds that emerge in 1 to 2 weeks at 21 to 24°C 

(70 to 75°F). Stem cuttings root easily without auxin. 

Iberis spp. Candytuft. Hardy annual and perennial 

species. Seed is germinated at 15 to 18°C (60 to 

65°F) in light. Cultivars are propagated by softwood 

cuttings in summer or plants are divided in fall. 

Impatiens spp. Touch-me-not, balsam. Impatiens are 

important bedding plants and include impatiens 

(l. walleriana), New Guinea impatiens (l. hawkeri), balsam 

(l. balsamina), and several new hybrids. They can 

be propagated by seeds or cuttings. Seed germination is 

at 24 to 25°C (75 to 78°F) and benefits from light (63). 

Light seeds for the first 3 days and then move to darkness 

until seedling emergence. Plants can be started by 

terminal cuttings treated with 2,500 ppm IBA under 

mist with bottom heat [22°C (72°F)]. Impatiens have 

also been micropropagated (283, 284). 

Incarvillea spp. Incarvillea. Hardy perennial producing 

large gloxinia-like flowers in the spring. Seed is germinated 

at 20°C (68°F). Divide in fall or, preferably, in 

spring. Basal cuttings taken in the spring can also be 

rooted. 

Ipomoea spp. Morning glory, ornamental sweet 

potato. Tender perennials grown as an annual. Seeds 

germinate within 1 week at 18 to 21°C (65 to 70°F). 

Notch seed coats or soak seeds overnight in warm water 

before planting. 

I. batatas. Sweet potato vine. Popular annual 

vine with bright yellow or dark purple foliage used in 

containers or for bedding. Cuttings are easily rooted 

without auxin under mist. 

Iresine spp. Bloodleaf. Tender perennial used as an 

indoor plant or outdoors as a container or bedding 

plant. Seeds germinate at 24°C (75°F) with light. 

Softwood cuttings root easily without auxin. 

Iris spp. (96). Perennials. There are several different 

groups of hardy or semi-hardy iris, which grow either from 

rhizomes or from bulbs. Rhizomes are divided after 

bloom. Discard the older portion and use only the vigorous 

side shoots. Leaves are trimmed to about 15 cm (6 in). 

Bulbous species follow a typical spring-flowering, 

fall-planting sequence. The old bulb completely disintegrates, 

leaving a cluster of various-sized new bulbs. 

These are separated and graded, the largest size being 

used to produce flowers, the smaller for further growth. 

Seeds, which are used to propagate species and to 

develop new cultivars, should be planted as soon as ripe 

after being given a moist-chilling period; germination 

is often irregular and slow. Removal of embryo from


the seed and growing it in artificial culture has yielded 

prompt germination in some cases. Iris can be micropropagated, 

which greatly hastens production of new 

cultivars over the customary division of rhizomes (155, 

161, 305). 

Ixia spp. Corn lily (92). Tender, summer- or fallflowering 

perennials grown from corms. In cold 

climates, these are dug in fall and stored over winter. 

Small cormels are removed and planted in the ground 

or in flats to reach flowering size, as is done with gladiolus. 


Ixora spp. (245). Ixora. Tender perennial used for 

indoor gardens. Several species are used in Hawaii as 

landscape and flowering pot plants. Many species are 

easy to propagate by cuttings. Difficult-to-root I. acuminata 

three-node cuttings had optimal rooting when 

given a 5-second dip of IBA-NAA, both at 2,500 ppm. 

Justicia spp. Shrimp plant (J. brandegeeana) and 

Brazilian plume (J. carnea) are tropical plants grown as 

landscape plants where hardy and indoor flowering pot 

plants. Propagation is from softwood cuttings with bottom 

heat [24°C (75° F)]. 

Kalanchoe blossfeldiana. A tropical succulent perennial 

grown as an indoor flowering pot plant. Plants can 

be propagated by cuttings or tissue culture, but they are 

more commonly propagated from terminal cuttings. 

Cuttings are rooted easily under mist or poly tent with 

bottom heat [22°C (72°F)]. Disease-free cuttings are 

available from commercial specialists that have been 

cleaned in tissue culture (31). Plants can also be micropropagated 

(270). 

K. diagremontiana. (formerly Bryophyllum). A 

succulent plant grown for its interesting habit of forming 

plantlets (often called foliar embryos) along the 

margin of the leaf. These plantlets can be removed for 

propagation. 

Kangaroo Paw. See Anigozanthus spp. 

Kirengeshoma palmata. Yellow wax bells. Herbaceous 

perennial producing pendulous yellow blossoms for 

shady garden beds. Propagated by crown division when 

plants are dormant. 

Knautia spp. Herbaceous perennial plants, many of 

which were formerly in Scabiosa. Used in perennial 

beds. Propagation is from dormant crown division or 

stem cuttings from new growth in spring. 

Kniphofia hybrids (K. tritoma) (286). Torch lily or 

poker plant. Perennials used as specimen plants, borders, 

and cut flowers. Seeds germinate at 18 to 24°C 


(65 to 75°F) in light. Many of the cultivars are propagated 

by crown division. 

Lachinelia spp. Cape cowslip (92). Tender bulbous 

perennials most often seen as container plants in display 

areas. Propagated by bulb offsets or micropropagation 

(176). 

Lamiastrum galeobdolan. Yellow archangel. Hardy 

perennial used as a ground cover for shade gardens. 

Grown for the attractive variegated foliage. Only cultivars 

are grown and these are usually propagated by softwood 

cuttings. Division is also possible. 

Lamium maculatum. Spotted deadnettle. Hardy 

perennial with trailing stems that are used as a ground 

cover for shade. Propagation is by stem cuttings treated 

with 2,500 ppm IBA under mist. Plants can also be 

divided. 

Lantana sellowiana, L. camara. Lantana. Tender 

perennials treated as landscape plants where hardy and 

as annuals where tender. Lantana has become invasive 

in some tropical countries. Seeds germinate at 20°C 

(68°F). Softwood cuttings root easily under mist. 

Lathyrus latifolius. Perennial pea vine. Hardy perennial. 

Seeds germinate at 13 to 18°C (55 to 65°F). 

Clumps may be divided. 

L. odoratus. Sweet pea. Hardy annual grown for 

garden display or cut flowers. Seed germinates in 

2 weeks at 20°C (68°F). Notching seed or soaking in 

warm water may hasten germination. Plant outdoors 

in fall where winters are mild, in spring where winters 

are severe. 

Lavandula spp. Lavender. Half-hardy perennial 

native to Mediterranean. Essential oils from these 

plants are important for the perfume industry. Seeds 

germinate at 18 to 24°C (65 to 75°F) in light. Stem 

cuttings are treated with 2,500 ppm IBA and rooted 

under mist with bottom heat. Divide clumps in the fall. 

Micropropagation is from hypocotyl explants (55) or 

leaf-derived callus (300). 

Lavatera trimestris. Tender herbaceous perennials 

used as annuals. Plants produce showy hibiscus-like 

flowers. Seeds germination is at 21°C (70°F). 

Leonotis leonurus. Lion’s ear. Tender perennial usually 

grown as a container plant, greenhouse displays, or in 

garden beds. Propagation is from stem cuttings taken 

prior to flowering. 

Leontopodium alpinum. Edelweiss (223). Hardy 

perennial. Mounded plants with silvery leaves and 

unique flowers. Seeds germinate at 20 to 22°C (68 to



72°F). Division is also possible. Plants can also be multiplied 

in tissue culture (146). 

Lespedeza spp. Bushclover. Considered an herbaceous 

perennial in more northern latitudes or a semiwoody 

shrub in the southern United States. Excellent 

landscape shrub for massing and screening with its 

bluegrass foliage and purple flowers. Seeds can be 

direct-sown after harvest or scarified with a 15-minute 

acid treatment if stored. Roots easily from softwood 

cuttings with 1,000 ppm IBA. 

Leucanthemum xsuperbum (formerly Chrysanthemum 

superbum). Shasta daisy. Hardy perennial but often 

treated as a biennial, since it is short-lived. Propagated by 

seeds at 18 to 21°C (65 to 70°F) that emerge in about 1 

week. Division is from side shoots that have roots. Can 

be commercially micropropagated. 

Leucocorne ixioides. Glory of the sun. Tender bulb 

grown as a pot plant or for cut flowers. Propagation is 

from bulb offsets. 

Leucojum spp. (92). Spring snowflake. Hardy perennial 

bulb. Bulbs have been collected for sale from native 

populations to the point of endangerment. Plants produced 

from seed take 4 to 5 years to flower. 

Propagation is normally done by separating bulbs, 

which is done by digging bulbs after foliage has turned 

brown. Can be micropropagated (73, 277). 

Lewisia cotyledon. Semi-hardy perennial commonly 

seen in rock, alpine, or dish gardens. Seeds germinate at 

21°C (70°F) (2). Cuttings from the basal rosette are 

possible. Leaf cuttings can also be used to produce new 

plants. 

Liatris spp. Gayfeather (203). Hardy perennials used in 

garden beds, naturalized prairies, as well as cutflowers 

(16). Seeds may benefit from stratification at 4°C (34°F) 

for 6 weeks and will germinate at 21°C (70°F), but flower 

development can take 2 years. Asexual propagation is by 

woody corms or rhizomes, which are divided in the 

spring (286). L. spicata has been micropropagated (289). 

Ligularia spp. Large herbaceous perennials producing 

yellow composite flowers and ornamental foliage. Seeds 

germinate at 18°C (65°F) in dark. Plants can also be 

divided. 

Lilium spp. (30, 204). Lily. Hardy perennials. These 

are spring- and summer-flowering plants grown from 

scaly bulbs; most have a vertical axis, but in some 

species growth is horizontal with a rhizomatous structure. 

Lilies include many species, hybrids, and named 

cultivars. Seed propagation is used for species and for 

new cultivars. Seeds of different lily species have different 

germination requirements (252). 

Immediate seed germinators include most commercially 

important species and hybrids (L. amabile, 

L. concolor, L. longiflorum, L. regale, L. tigrinum, Aurelian 

hybrids, Mid-Century hybrids, and others). Germination 

is epigeous; shoots generally emerge 3 to 6 weeks after 

planting at moderately high temperatures. Treat seeds 

with a fungicide to control Botrytis. Sow 3/4 inches deep 

in flats during winter or outdoors in a seed bed in early 

spring. Dig the small bulblets in fall, sort for size, and 

replant with similar sizes together. Plants normally grow 

2 years in a seed bed and 2 years in a nursery row before 

producing good-sized flowering bulbs. 

Another group consists of the slow seed germinators 

of the epigeal type (L. candidum, L. henri, Aurelian 

hybrids, and others), in which seed germination is slow 

and erratic; the procedures used are essentially the same 

as described above. The most difficult group to propagate 

are the slow seed germinators of the hypogeous 

type (L. auratum, L. bolanderi, L. canadense, L. martagon, 

L. parvum, L. speciosum, and others). Seeds of this 

group require 3 months under warm conditions for the 

root to grow and produce a small bulblet, then a cold 

period of about 6 weeks, followed by another warm 

period in which the leaves and stem begin to grow. This 

sequence can be provided by planting the seeds outdoors 

in summer as soon as they are ripe, or by planting 

seeds in flats and then storing under appropriate conditions 

to provide the required temperature sequence. 

These procedures are described in Chapter 15. L. longiflorum 

can also be propagated by leaf cuttings. 

Vegetative methods of propagation include natural 

increase of the bulbs, such as bulblet production on 

underground stems (either naturally or artificially), aerial 

stem bulblets (bulbils), or scaling. Outer and middle 

scales are used for scale propagation to increase the 

number of forcible commercial bulbs (200). 

Lilies can be micropropagated from bulb scales 

(288) and pedicels (198). L. longiflorum can also be 

propagated by leaf cuttings. 

Limonium spp. Statice. L. sinuatum is a perennial 

herb, native to the eastern Mediterranean, which is 

grown commercially around the world as a cut flower 

for both fresh- and dry-flower arrangements. L. latifolia 

is a hardy perennial. Plants are propagated by seeds 

that germinate at 21°C (70°F). Statice has been micropropagated 

(54, 138). 

Linaria spp. Toadflax, butter and eggs. Hardy annual 

and perennials. Seeds germinate in 1 to 2 weeks at 

18°C (65°F) in light. Perennial species may take 2 years


to produce bloom from seed. Perennial types can be 


Linum spp. Flax. Hardy annual and perennial species 

with blue or yellow flowers. Used in perennial beds and 

rock gardens. Seeds germinate in 2 to 3 weeks at 18 to 

24°C (65 to 75°F). Divide clumps of perennial species 

in fall or spring. 

Liriope spp. Lily turf. Hardy perennial. Vigorous 

ground cover. Can be propagated by seed or division. 

Seeds have morphological dormancy and require warm 

stratification [21 to 30°C (70 to 85°F)] for germination 

(110). However, commercial propagation is by division 

in spring or autumn. Plants can be micropropagated 

(119). 

Lisianthus. See Eustoma. 

Lithodora diffusa. Semi-hardy prostrate perennial 

grown for intense blue flowers. Propagated by stem cuttings 

in summer or from division. 

Lithops spp. Living stones. Interesting succulents with 

plants adapted to mimic stones. Propagation is from 

seeds sown at 18 to 24°C (65 to 75°F). Some species 

produce offsets that can be divided. 

Lobelia erinus. Lobelia. Tender perennial grown as an 

annual. Seeds germinate at 24 to 26°C (75 to 80°F), 

but seedling growth is slow. May respond to light (18). 

Mature plants, if potted in the fall and kept in greenhouse 

over winter, can be used to provide new growth 

for cuttings to be taken in late winter. Commercial cuttings 

are treated with 2,500 ppm IBA under mist. 

Lobelia cardinalis (cardinal flower), L. 

siphilitica (blue cardinal flower) and hybrids. 

Hardy and half-hardy perennials. Seeds germinate at 20 

to 24°C (68 to 75°F). Species self-seeds. Divide clumps 

in fall or spring. 

Lobularia maritima. Sweet alyssum (223). Perennial 

grown as a hardy annual. Seed germinates in 1 to 

2 weeks at 26 to 28°C (75 to 82°F) in light and blooms 

appear in 6 weeks. Often seeded with more than one 

seed per plug for better pack development. 

Lunaria annua. Honesty or money plant. Biennial, 

sometimes grown as an annual. Seeds germinate at 

20°C (68°F). 

L. rediviva. Hardy perennial. Propagated at 

20°C (68°F). Also increased by dormant division. 

Lupinus spp. and hybrids. Hardy annuals and perennials. 

All lupines have physical seed dormancy and 

require scarification. Seeds germinate at 20°C (68°F). 


L. texensis. (Texas bluebonnet) L. texensis has 

been micropropagated from cotyledonary node 

explants (302). Sow seeds in spring or summer, or 

propagate by cuttings taken in early spring with a small 

piece of root or crown left attached. 

Lychnis spp. Campion. Mostly hardy perennials, but 

some are grown as annuals or biennials. Seeds germinate 

at 20°C (68°F) or propagated from dormant 

crown divisions. 

Lycoris spp. Spider lily, surprise lily (92). Tender and 

semi-hardy perennials from a tunicate bulb. Propagation 

is by bulb offsets, which are removed when the dormant 

bulbs are dug. These are replanted to grow larger. Bulb 

cuttings can also be used for increase. Micropropagation 

by twin scaling has also been developed (152). 

Lysimachia spp. Loosestrife. Hardy perennial. 

Vigorous plants with striking white or yellow flowers. 

Trailing plants are grown for their colorful foliage. Can 

be propagated from seed, division, or softwood cuttings. 

Seeds germinate at 18 to 21°C (65 to 70°F). Terminal 

stem cuttings root easily under mist without auxin. 

Lythrum salicaria. Purple loosestrife. Hardy perennial. 

Long-blooming plants produce purple flowering 

spikes. Lythrum can be an invasive weed in wet habitats 

and some states prohibit its use. Propagation is easy 

from softwood cuttings. Division is possible but difficult, 

because the roots are woody. 

Macleaya cordata. Plume poppy. Aggressive, hardy 

perennial from a creeping rhizome. Produces bold 

foliage and large plumes of small white flowers. 

Propagation is from division of the rhizome. 

Malva alcea. Hollyhock mallow; and M. moschata. 

Musk mallow. Drought-tolerant perennials utilized in 

border plantings. Seeds germinate within 2 weeks at 

21°C (70°F). Plants can also be propagated by division. 

Mammillaria. See Cactus. 

Maranta leuconeura. Prayer plant. Tender perennials 

grown as indoor potted plants. They are normally 

propagated asexually by stem cuttings because seeds are 

difficult to germinate. Cuttings are rooted in humidity 

tents for 4 to 6 weeks. M. leuconeura ‘Kerchoviana’ can 

be micropropagated (103). 

Marigold. See Tagetes spp. 

Matteuccia. Ostrich fern. See Fern. 

Matthiola incana. Common stock (223); M. 

longipetala bicornis. Evening scented stock. Perennials 

grown as biennial or annual plants most often used as



cut flowers or for bedding. Seed germinates at 18 to 

21°C (65 to 70°F) and may respond to light (18). Seeds 

are sown in summer or fall for winter bloom, in late 

winter indoors for spring bloom, or outdoors in spring 

for summer bloom. 

Mazus reptans. Hardy perennial that forms a creeping 

mat of foliage and purple-blue flowers. Propagated 

from division or cuttings of the creeping stem. 

Meconopsis spp. A group of alpine annual and shortlived 

perennials. Poppy-like flowers can be white, red, 

yellow, or blue depending on the species. Must have 

cool summers to survive. Seeds germinate at 13°C 

(55°F). Most often the seeds are sown in a cold frame 

in fall for spring emergence. Perennial plants can also 

be divided before growth begins in spring. 

Melampodium paludosum. Annual. Rounded plants 

produce yellow daisy-like flowers throughout the growing 

season. Seeds germinate at 18°C (65°F). Self-sowing 

can be a problem in the garden. Plants also root from 

softwood cuttings. 

Mertensia spp. Hardy perennial plants usually grown 

in woodland gardens but also at home in the perennial 

bed. M. virginiana (currently M. pulmonarioides) 

Virginia blue bells produces nodding blue flowers early 

in the spring. Propagation is most often from division 

in dormant plants. 

Mesembryanthemum spp. See Succulents. 

Mimulus spp. Monkey flower. Includes many species 

of tender to hardy plants. Mostly perennials but sometimes 

grown as annuals. Seeds germinate at 15 to 21°C 

(60 to 70°F). Softwood cuttings taken from young 

shoots can be rooted under mist. 

Miscanthus sinensis. Maiden grass. There are many 

cultivars of this popular perennial grass. They make 

excellent specimens in the landscape with their showy 

feathery inflorescences. Cultivars are propagated by 

division. Miscanthus is a warm-season grass and should 

be divided in late spring. Miscanthus can be micropropagated 

(124). 

Molluccella laevis. Bells of Ireland. Half-hardy annual 

grown as a garden plant or cut flower. Seed germinates 

at 10°C (50°F) but may do better with 30°C (86°F) 

days alternating with 10°C (50°F) nights (223). Plants 

can be difficult to transplant. 

Monarda didyma. Bee balm (286). A perennial garden 

plant native to eastern North America. Can be 

propagated by seed, which germinates at 16 to 21°C 

(60 to 70°F). May benefit from a brief (1 week) chilling 

stratification. Can also be propagated by softwood cuttings 

or by crown division. 

Monstera deliciosa. Swiss cheese plant. Cut-leaf 

philodendron. Easily propagated by rooting sections of 

the main stem, by stem cuttings, or by air layering. 

Seeds germinate at 21 to 29°C (70 to 85°F). 

Muscari spp. Grape hyacinth (255). Hardy perennials 

from tunicate bulbs. Plants bloom in spring; bulbs 

become dormant in fall when they are lifted and 

divided by removing bulb offsets. Seed propagation can 

also be used. Bulb scooping and scoring produce bulb 

offsets. Micropropagation is easy from leaves, scales, or 

flower parts (231). 

Mussaenda erythrophylla. Red Flag Bush. Tropical 

evergreen perennials used as a landscape plant where 

hardy and as a container plant in other regions. Flowers 

are subtended by colorful bracts. Propagation is from 

stem cuttings with bottom heat (275). Plants can be 


Myosotis sylvatica. Forget-me-not. Hardy biennial or 

short-lived perennial. Grown for its blue or pink flowers 

in the spring. Plants may naturalize from seeds. 

Seeds germinate at 20°C (68°F). Sow in summer and 

transplant to permanent location the following spring. 

M. scorpioides is a perennial started from seed; division 

in spring is also used. 

Narcissus. Daffodil (135). Hardy perennials; springflowering 

tunicate bulbs. Vegetative propagation procedures 

are described in Chapter 15. Commercial propagation 

is mainly from natural bulb offset production. 

Vegetative techniques include twin scaling, chipping 

(almost the same method as twin scaling, except that 

the bulb is cut across the root plate into 8 to 

16 pieces with up to 2 bulbils developing per section), 

and micropropagation (73, 136, 150). 

Nasturtium. See Tropaeolum majus. 

Nelumbo lutea. American lotus; N. nucifera. Sacred 

Lotus. Aquatic plants for water gardens. Lotus produces 

one of the longest-lived seeds, which have physical dormancy 

and must be scarified. Seeds germinate readily at 

24°C (75°F). Lotus is usually propagated vegetatively 

through rhizome division. Rhizome cultures have been 

established in vitro from excised embryos (167). 

Nemesia strumosa. Capejewels. Half-hardy annual 

used as bedding plants. Seeds germinate at 13 to 18°C 

(55 to 65°F) in darkness. Temperatures above 18°C 

(65°F) can inhibit germination. Terminal stem cuttings 

root easily under mist without auxin.


Nemophila spp. Baby blue eyes. Low-growing native 

North American annuals used as bedding plants. 

Seeds germinate at 18°C (65°F) and require darkness 

to germinate. 

Neoregilia. See Bromeliads. 

Nepenthes spp. A large group of carnivorous plants 

producing pitchers to trap insects. Traps are formed at 

the tips of tendrils that extend from the midrib of the 

leaves. Propagation is from seeds at 27°C (81°F), leaf or 

stem cuttings (68), and tissue culture (248). 

Nepeta spp. Catmint. Hardy perennial. Seeds germinate 

at 20°C (68°F). Softwood cuttings of non-flowering 

side shoots taken in early summer root readily. Plants 

may be divided in spring, using newest parts and discarding 

older portion of clumps. 

Nerine spp. (303). A tender, perennial tunicate bulb. 

Lanscape bulb also used as a cut flower crop. 

Propagation is from offsets or bulb cuttage, but mostly 

by twin scaling. Tissue culture is possible from scales, 

lateral buds, and the young flower stalk (86). 

Nicotiana spp. Flowering tobacco. Half-hardy annuals 

with bright fragrant flowers. Seeds germinate at 24°C 

(75°F) and may respond to light (18). Stem cuttings 

root readily and plants are easily micropropagated. 

Nierembergia spp. Cupflower (223). Tender perennial, 

sometimes grown as an annual. Seeds germinate at 

21°C (70°F). Softwood cuttings removed from new 

growth in spring root readily. Clumps can be divided. 

Nigella damascena. Love-in-a-mist. Herbaceous 

annuals grown as bedding plants or as cut flowers for 

the interesting seed pods. Seeds germinate at 18 to 

24°C (65 to 75°F). 

Nolana paradoxa. Prostrate, annual plant with flowers 

that resemble small petunia blossoms. Seeds germinate 

at 20 to 22°C (68 to 72°F). Can also be propagated 

from stem cuttings. 

Nymphaea spp. Water lily. Consists of numerous 

species and many named cultivars. Plants grow as rhizomes. 

Clumps are divided in spring. Seeds are used to 

grow species and to develop new cultivars. Tropical 

water lily hybrids and species grow from tubers. Seeds 

do not reproduce hybrids. Both kinds of seeds are 

planted 2.5 cm (1 in) deep in sandy soil, then 

immersed in water 3- to 4-inch deep. Hardy species 

should be started at 16°C (60°F), tropical species at 21 

to 27°C (70 to 80°F). Vegetative propagation is either 

from small tubers that can be removed from old tubers 

in fall or from small epiphyllous plantlets growing from 


the leaf (268). Micropropagation is also possible 

by using epiphyllous plantlets as explants (162). 

N. ‘Gladstone’ production can be extended by photoperiod 

control (169). 

Ocimum basilicum. Basil. Annual plants usually 

reserved for the herb garden, but numerous colored leaf 

forms are available for the flower garden. Seeds germinate 

in 1 week at 21°C (70°F). Stem cuttings also root 

easily. 

Oenothera spp. Evening-primrose. Hardy perennials, 

but some kinds are biennial. Seeds germinate at 21 to 

26°C (70 to 80°F). Plants can also be increased by dormant 

crown divisions. 

Ophiopogon japonicus. Mondo grass. Hardy perennial. 

Evergreen ground cover. Propagation is by division in the 

spring or fall. Plants can be micropropagated (119). 

Opuntia spp. Prickly pear cactus. Hardy perennial. 

The only cactus hardy to the northern United States. 

Propagation is from seed, division, or cuttings (191). 

See Cactus. 

Orchids (217, 261, 285). Many genera, hybrids, and 

cultivars are cultivated, and many more are found in 

nature. Some, such as Aerides, Arachnis, Phalaenopsis, 

Renanthera, and Vanda, exhibit a monopodial habit of 

growth. This means they are erect and grow continuously 

from the shoot apex and can be propagated by tip 

cuttings. Adventitious roots are produced along the 

stem and inflorescences are produced laterally from leaf 

axils. Most others including Brassovola, Calanthe, 

Cattleya, Cymbidium, Laelia, Miltonia, Odontoglossom, 

Oncidium, and Phalus have a sympodial habit of 

growth, are procumbent, and do not grow continuously 

from the apex. Their main axis is a rhizome in 

which new growth arises from offshoots or “breaks.” 

Pseudobulbs are usually present on plants of this type. 

Many orchids are epiphytes (i.e., air plants), typically 

growing on branches of trees. Others (Cypripedium and 

Paphiopedilum) are terrestrial and grow in the soil (12). 

Epiphytic Orchids. Seed propagation is mainly 

used for hybridization. Many important cultivars are 

seedling hybrids, either from species or between genera, 

resulting from controlled crosses of carefully selected 

parents. Many such important crosses are between 

tetraploid and diploid parents to produce triploids. 

These offspring are sterile and are not usable as parents. 

Seedling variation occurs, since orchids are heterozygous. 

Five to seven years are required for a seedling 

plant to bloom. Orchid flowers are hand-pollinated. 

A seed capsule requires 6 to 12 months to mature.



A single capsule will contain many thousands of tiny 

seeds with relatively underdeveloped embryos. In vitro 

culture is universally used for seed propagation. (The 

procedure is described in Chapter 18.) Knudson’s C 

medium is usually used. Arditti (12, 13) has summarized 

the many experiences of testing various nutritional 

and other factors for orchid seed germination. 

Orchid seed can be stored for many years if held in 

sealed containers over calcium chloride at about 2°C 

(36°F). Vegetative methods for orchids are generally 

slow, difficult for many genera, and usually too lowyielding 

for extensive commercial use. Sympodial 

species are increased by division of the rhizome while it 

is dormant or just as new growth begins. Four or five 

pseudobulbs are included in each section. “Back-bulbs” 

and “greenbulbs” can be used for some genera. 

Orchids with long canelike stems, such as 

Dendrobium and Epidendrum, sometimes produce offshoots 

(“keiki”) that produce roots. Offshoots can also 

be produced if the stem is cut off and laid horizontally 

in moist sphagnum or some other medium. Flower 

stems of Phaius and Phalaenopsis can be cut off after 

blooming and handled in the same way. A drastic 

method of inducing offshoots is to cut out or mutilate 

the growing point of Phalaenopsis, remove the small 

leaves, and treat the injured portion with a fungicide. 

Offshoots may then be produced. Monopodial species 

can be propagated by long (30 to 37 cm) tip cuttings 

with a few roots already present. Air layering is also 

possible. Vegetative propagation by proliferation of 

shoot-tip (meristem) cultures in vitro has revolutionized 

orchid propagation, particularly for Cymbidium, 

Cattleya, and some other genera (14, 217). The shoot 

growing point is dissected from the plant and grown on 

a special, sterile medium; a proliferated mass of tissue 

and small protocorms develops, which can be divided 

periodically. Many thousands of separate protocorms 

can be developed in this way within a matter of 

months, each of which will eventually differentiate 

shoots and roots to produce an orchid plant (14). The 

procedure is described in Chapter 18. Vanilla planifolia, 

which is an orchid, essential for its oil, that grows as 

a vine, is normally propagated commercially by cuttings; 

nodal stem explants of this species were successfully 

micropropagated with BA and microshoots rooted 

ex vitro (179). 

Terrestrial Orchids. These orchids can be difficult 

to propagate because they require a symbiotic relationship 

with an appropriate mycorrhizal fungus. In 

vitro seed germination using techniques similar to those 

used with epiphytic orchids has been successful both 

with and without fungal assistance (11). However, 

these procedures have not been extensively used commercially. 

Sowing seeds in pasteurized potting mixes 

containing mycorrhizal fungi has been successful and 

offers commercial potential (242). 

Origanum spp. Oregano, Dittany of Crete. Tender 

perennials usually produced as annuals. This genus 

contains the culinary herbs oregano and marjoram, but 

also contains showy ornamentals grown as bedding or 

container plants. Seeds germinate at 21°C (70°F). 

Ornithogalum spp. Star of Bethlehem (92). 

Herbaceous perennials that grow from tunicate bulbs. 

They are grown as garden plants, but are most important 

as cut flowers and seasonal pot plants. Plants have 

been propagated by seeds, leaf cuttings, bulb divisions, 

and tissue culture. Emerging leaves can be taken as leaf 

cuttings with plant regeneration taking place under 

mist (see Chapter 15). Micropropagation is also practiced 

(307, 325). 

Osmunda spp. See Fern. 

Osteospermum spp. Tender annual and perennial 

plants grown as bedding or container plants. Flowers 

are daisy-like with some interesting cultivars that have 

spoon-type ray florets. Seeds germinate at 21 to 24°C 

(70 to 75°F). Tip cuttings (99) are treated with 3,000 

ppm IBA under mist with bottom heat 22°C (72°F). 

Oxalis spp. Shamrock or wood sorrel (92). 

Herbaceous perennials used in the garden or grown as a 

seasonal pot plant. Oxalis is an interesting and diverse 

group of plants. Some members of this genus are perhaps 

the only dicot species that produces a bulb. 

Others produce tubers or rhizomes. Propagation is usually 

from offsets of the bulbs or division of the tubers or 

rhizomes. Can be micropropagated (170). 

Pachysandra spp. See Chapter 20. 

Paeonia spp. Paeonia hybrids (P. hybrida), fernleaf 

peony (P. tenuifolia), tree peony [P. suffructicosa 

(P. arborea)]. Hardy perennials native to China used for 

specimen plants in borders and as cut flowers. Seed 

propagation is difficult, taking 5 to 7 years to produce a 

flowering plant from seed (286). Germination may 

take 1 to 2 years to meet epicotyl dormancy requirement. 

Seeds are sown in fall for cold stratification 

requirement during the winter. Roots develop during 

the first summer, and shoots develop the second spring. 

Plants developed from seed are generally not trueto-type. 

Another method is to collect seeds before they 

become black and completely ripe. Do not allow them 

to dry out; sow in pots, which should be buried in the


ground for 6 to 7 weeks. Roots will develop; dig up and 

plant in a protected location or under mulch over winter. 

Best propagation method for herbaceous peonies is 

to divide clumps in fall; each tuberous root should have 

at least one bud or “eye,” preferably three to five. 

P. suffruticosa is wedge grafted in late summer 

onto a herbaceous (P. lactiflora) understock (254). 

Peonies can be micropropagated (3, 45, 50). 

Pansy. See Viola. 

Papaver nudicaule. Iceland poppy. Hardy perennial 

often grown as a biennial. Seeds germinate in 1 to 2 

weeks at 18 to 24°C (65 to 75°F). Sow in permanent 

location in summer for bloom next year. 

P. orientale. Oriental poppy. Hardy perennial. 

Very fine seeds, which may respond to light, should be 

covered very lightly (18). Seeds germinate in same time 

as P. nudicaule. Cultivars are propagated by root cuttings. 

Dig when leaves die down in fall, cut into 7.5- to 

10-cm (3- to 4-in) sections, and lay horizontally in a 

flat covered by 2.5 cm (1 in) of a sandy greenhouse substrate. 

Root cuttings are transplanted in spring. Or dig 

plants in spring, prepare root cuttings, and plant 

directly in a permanent location. 

P. rhoeas. Corn poppy, Shirley poppy. Hardy 

annual. Seed germinates at 13°C (55°F). Sow in late 

summer for early spring bloom or in early spring for 

summer bloom. 

Pelargonium spp. Geranium. A group of tender 

perennials grown as bedding plants, hanging baskets, 

and seasonal pot plants. Plants are propagated by seeds 

or cuttings. 

Pelargonium xdomesticum. Regal Geranium. 

Grown primarily as a cool-season conservatory plant or 

as a seasonal pot plant. If used in the garden, summer 

temperatures must be cool to keep plants in bloom. 

Propagation is from stem cuttings under mist with bottom 

heat [21 to 24°C (70 to 75°F)] from disease-free 

stock plants. 

P. xhortorum. Geranium. Started by cuttings 

and by seed. Traditionally propagated by cuttings, 

which root easily with bottom heat, but Pythium and 

Botrytis infection can be serious problems. Pathogenfree 

stock, identified by culture indexing, should be 

used and can be supplied by specialists (298). There 

may be practical value in applying ABA in the shipment 

and storage of geranium cuttings (17). 

In the mid-1970s, large-scale seed propagation 

of geraniums began with the introduction of certain 


cultivars that would grow from seed to flower in 14 to 

16 weeks. Seeds germinate best at about 21 to 24°C 

(70 to 75°F) in medium greenhouse substrate (15). 

Plant growth regulators (like cycocel) are utilized in 

greenhouse to produce compact, early-flowering, 

well-branched plants (258). In vitro propagation has 

been developed and can be used for virus elimination 

in stock plants (67, 98). 

P. peltatum. Ivy geranium. Popular as a window 

box or hanging basket plant. Propagation is from terminal 

stem or leaf-bud cuttings handled as described 

for other geraniums. 

Pennisetum spp. Fountain grass. Perennial grasses with 

feathery inflorescences. They are propagated by division 

in late spring to early summer (81). Seeds germinate easily, 

and volunteers in the garden can be a nuisance. 

Penstemon spp. Beardtongue. Semi-hardy to hardy 

perennials, sometimes handled as annuals. Seeds germinate 

at 18 to 21°C (65 to 70°F), but growth can be 

slow and uneven; seeds may respond to light (18). 

Some species benefit from 8 weeks of stratification at 

15°C (59°F) (5). Plants started indoors in early spring 

and transplanted outdoors later may bloom the first 

year. Plants are usually short-lived. 

Softwood cuttings taken from non-flowering side 

shoots of old plants root readily. Make cuttings in fall 

to obtain plants for next season. Clumps may be 

divided. Penstemon can also be micropropagated from 

lateral buds used as explants (197). 

Pentas lanceolata. Star-cluster pentas. Tender perennial 

with clusters of white, pink, lavender or red starshaped 

flowers grown as a pot or bedding plant. Can be 

propagated from seeds or cuttings. Seeds germinate at 

21 to 22°C (70 to 72°F). Tip cuttings from nonflowering 

plants are treated with 1,000 ppm IBA 1 500 

ppm NAA and rooted under mist with bottom heat at 

[20 to 22°C (68 to 72°F)] (99). 

Peperomia spp. Tender perennials grown as indoor 

house plants and occasionally as bedding plants. 

Softwood stem, leaf-bud, or leaf cuttings root readily. 

Plants can also be divided. Peperomia can also be 

micropropagated from excised leaf explants (142) and 

petioles (243). 

Pericallis xhybrida. Florist’s cineraria (formerly 

Senecio cruentus) is a cool-season crop with true blue or 

lavender flowers grown as a seasonal pot plant. Seeds 

germinated at 20 to 22°C (68 to 72°F) will emerge in 2 

weeks in light (168). Plants are most often produced 

from seeds because vegetatively propagated plants can



show reduced vigor and flower size. Plants have been 

micropropagated (77, 126). 

Periwinkle. See Vinca minor. 

Persicaria spp. Fleeceflower or knot weeds. This genus 

now contains plants that were formerly Polygonum and 

Tovara. Versatile perennials and annuals used as ground 

covers, in rock gardens, planters, and hanging baskets. 

Generally propagated by division or seed. P. capitatum 

‘Magic Carpet,’ which is an excellent annual ground cover, 

is propagated by seed at 21 to 27°C (70 to 80°F). Other 

species (P. affine, P. amplexicaulis, and P. virginiana) are 

more commonly propagated by division. 

Pervoskia atriplicifolia. Russian sage. Hardy perennial. 

Large shrub-like perennial with silvery foliage and blue 

flowering spikes. Propagated from softwood cuttings. 

Petunia xhybrida. Petunia (65). Tender perennial 

often grown as an annual. Seeds germinate at 24 to 

25°C (75 to 78°F). Give light for the first 3 days then 

move to darkness until seedlings emerge. Several cultivars 

are propagated from stem cuttings that root easily 

under mist. Petunia is easily micropropagated from leaf 

segments (287). 

Philodendron spp. Tropical vines. Seeds germinate 

readily at about 25°C (77°F) if sown as soon as they are 

ripe and before they become dry. Vining types are 

propagated by single node leaf-bud or stem cuttings. 

Larger plants may be multiplied by air layering. Nonvining 

types are propagated from seeds or, more commonly, 


Phlomis russeliana. Jerusalem sage. Hardy perennial 

grown for pale yellow flowers on stiff, upright stems. 

Most commonly propagated by crown division or stem 

cuttings. 

Phlox spp. Phlox. Colorful herbaceous annual or perennial 

garden plants. Propagated by seeds or cuttings. 

Phlox divaricata. Sweet William. Hardy perennial. 

Expose seeds to cold during winter or chilling 

stratification before planting. Softwood cuttings taken 

in spring root easily. Divide clumps in spring or fall. 

Phlox drummondii. Annual phlox (65). Hardy 

annual. Seed germinate at 15 to 18°C (60 to 65°F). 

Initial seed germination occurs in either light or darkness, 

but light inhibits radicle growth, so it is common 

to germinate phlox in the dark (62). Start indoors for 

later outdoor planting, or outdoors after frost. 

Phlox paniculata. Garden phlox. Hardy perennial. 

Plants do not come true from seed. Sow seeds as 

soon as ripe in fall to germinate the next spring. Seed 

will germinate at 20°C (68°F). Grow plants one season 

and transplant in fall. Softwood cuttings taken from 

young shoots in spring or summer root easily, but are 

subject to damping-off if kept too wet. Garden phlox 

are often commercially propagated from root cuttings 

(195). Dig clumps in fall; remove all large roots to 

within 5 cm (2 in) of crown (which is replanted). Cut 

roots into 2-inch lengths and place in flats of sand; 

cover 13 mm (0.5 in) deep. Transplant next spring. 

Divide clumps in fall or spring. Phlox can be micropropagated 

using shoot explants (257, 292). 

Phlox subulata. Moss pink. Hardy perennial. 

Evergreen ground cover with profusion of blooms in early 

spring. Propagation is by division of dormant plants or 

softwood stem cuttings taken after plants finish blooming 

in the spring. Cuttings are treated with 1,000 ppm IBA 

under mist. Plants can be micropropagated (257). 

Physalis alkekengi. Chinese lantern. Hardy perennial 

grown for showy fruits shaped like orange paper 

lanterns. Seeds emerge in 2 weeks at 16 to 21°C (60 to 

70°F). Can be divided in the autumn. 

Physostegia virginiana. False dragonhead or lionsheart. 

A herbaceous perennial that is used as a fieldgrown 

cut flower crop (16). Seeds will germinate at 18 

to 21°C (65 to 70°F). This species can also be propagated 

by division. 

Pinguicula spp. Butterwort. Perennial carnivorous 

plants. Glandular hairs are produced on the leaves of 

these rosette plants to trap insects. An attractive flowering 

carnivorous plant. Propagation is from seed or 


Platycodon grandiflorus. Balloon flower. Hardy 

perennial. Long-lasting blue flowers that resemble balloons 

when in bud. Most commonly propagated by 

seeds that emerge in 1 to 2 weeks at 20 to 21°C (68 to 

70°F) with light. Plants can also be divided in spring. 

Plectranthus spp. Spurflowers. Tender herbaceous 

perennials related to coleus. Plants are primarily grown 

for their interesting foliage, but some have showy flowers. 

Propagation is primarily from stem cuttings with 

bottom heat (21 to 24°C; 70 to 75°F) that root easily 

without auxin. 

Poinsettia (Euphorbia pulcherrima). See Chapter 20. 

Polemonium spp. Jacob’s ladder. Hardy perennial. In 

spring, blue or white flowers appear on plants with a 

leaflet pattern that resembles a ladder. Seeds germinate 

at 21°C (70°F). Plants can also be multiplied by crown 

division and stem cuttings.


Polianthes tuberosa. Tuberose (34). Tender bulbous 

perennial. Propagated by removing offsets at planting 

time. The small bulbs take more than 1 year to flower. 

Divide clumps every 4 years. Plants can be micropropagated 

(44). 

Poliomintha longiflora (153). Mexican oregano. Has 

small evergreen leaves that smell like the spice oregano 

and is a striking landscape plant that produces light 

lavender flowers throughout the summer. It is easily 

rooted from stem cuttings. 

Polygonatum spp. Solomon’s seal. Hardy perennials. 

Used in wildflower and perennial gardens. Propagation 

is by seed or division. Cultivars are propagated by 

dividing rhizomes in the spring. 

Portulaca spp. Moss rose, flowering purslane. Halfhardy 

annual used as a bedding or container plant. Seeds 

germinate at 24 to 27°C (75 to 80°F) and may respond 

to light (18). Can also be propagated by tip cuttings. 

Potentilla spp. Cinquefoil. Hardy perennial. 

Creeping perennials with attractive blooms. Can be 

propagated by seed, division, or stem cuttings. P. 

nepalensis is a common garden perennial and is grown 

from seed germinated at 21°C (70°F). 

Pothos. See Epipremnum. 

Primula spp. Primrose. A group of cool-season perennials 

used in the rock or perennial garden. Some species 

and hybrids used as seasonal pot plants. Most primroses 

are propagated by seed. Seed germination can be erratic. 

Seeds generally require light, and germination temperature 

should be below 21°C (70°F). Erratic germination 

may be related to seed dormancy, and germination has 

been enhanced by a pregermination treatment with gibberellic 

acid (100). Micropropagation is possible (35). 

P. xpolyantha and P. vulgaris (syn P. aucale). 

Hardy perennials grown outdoors or used as seasonal 

pot plants. Seeds are slow to germinate and can take up 

to 30 days. Germination is at 16 to 18°C (60 to 65°F), 

but some species may require lower temperatures (80, 

107). It is best to collect and sow seeds as soon as they 

are ripe in the fall. Clumps can be divided just after 

flowering. 

Primula malacoides. Fairy primrose. Seeds will 

germinate in 2 to 3 weeks at 15 to 18°C (59 to 65°F). 

Primula obconica. Primrose. Tender perennial 

grown as an annual. Seeds germinate well in a cool 

greenhouse or after 3 to 4 weeks at 18 to 20°C (65 to 

68°F). The very tiny seeds respond to light and should 

not be covered. 


Primula sinensis. Chinese primrose. Seeds will 

germinate within 3 weeks at 20°C (68°F). In these 

species, double-flowering cultivars do not produce 

seeds but are propagated by cuttings taken in spring, or 

by division. 

Pulmonaria spp. Lungwort. Hardy perennial grown 

for their attractive spotted or silvery foliage on plants 

adapted to the shade garden. Common companion 

plant to hostas. Can be propagated by division, root 

cuttings (48), or tissue culture. Tissue culture propagation 

and the introduction of new cultivars has increased 

the availability of lungworts (290). 

Pulsatilla spp. Pasque flower (formerly Anemone pulsatilla). 

Hardy perennial with showy anemone-like 

flowers and feathery seed heads. Seed germination is at 

20°C (68°F) but may be sensitive to high temperature. 

Plants can be divided or propagated from root. 

Puschkinia scilloides. Striped squil (92). Hardy 

perennial bulb. Propagation is the same as Scilla. 

Ranunculus spp. Buttercup (210). A group of herbaceous 

perennials produced on tuberous roots or rhizomes. 

Plants are used as annual or perennial garden 

plants, seasonal pot plants, and cut flowers. Commonly 

propagated by seeds germinated at 20°C (68°F). Divide 

perennial types while dormant in spring or fall. 

Ranunculus asiaticus. Turban or Persian ranunculus. 

Tender perennial. Plants are most commonly 

propagated from seeds that germinate at 15 to 17°C (58 

to 62°F). Plants can also be multiplied by division of the 

tuberous root, or micropropagated (172, 211). 

Ratibida spp. Prairie coneflower. Hardy perennial 

producing yellow coneflowers. Most often used in 

native prairie plantings and wildflower mixes. Seed germination 

is at 21 to 24°C (70 to 75°F) and may benefit 

from several weeks of chilling stratification. Plants 

can be divided. 

Reseda odorata. Mignonette. Hardy annual. Seeds 

should not be covered; Seed germination is at 12°C 

(54°F), and seeds may respond to light (18). 

Rhipsalidopsis spp. Easter cactus. Propagation same 

as Epiphyllum. 

Ricinus communis. Castor bean. Soak seeds in water 

for 24 hours or nick with file before planting. Seed germination 

is at 21°C (70°F). Seeds are poisonous. 

Rodgersia spp. Featherleaf, Rodgersflower. Perennial 

for moist border with attractive foliage and ornamental 

flowers. Propagation is by seeds or division.



Rudbeckia spp. Black-eyed Susan, coneflower. Hardy 

annual, biennial, and perennial species. Seeds germinate 

in 2 to 3 weeks at 21 to 24°C (70 to 75°F). 

Perennial kinds are propagated by crown division. 

Plants often re-seed naturally. Seed priming can 

improve germination (113). 

Rumex sangineus. Red-veined dock. Semi-hardy 

perennial grown for the interesting red-veined pattern 

on leaves. Propagation is from seed germinated at 

20°C (68°F). 

Saintpaulia ionantha. African violet (159, 181, 324). 

Tropical perennial. Propagation is by seed, division, or 

cuttings. The very fine seeds, which germinate at 30°C 

(86°F), should not be covered. Seedlings are subject to 

damping-off. Vegetative methods are necessary to maintain 

cultivars. Leaf cuttings (blade and petiole) are easily 

propagated using a rooting medium at 25°C (75°F) and 

air temperature at 18°C (64°F) (260). Variegated leaf 

cultivars that do not come true from leaf cuttings 

should be propagated by crown divisions or tissue culture 

(271). Rapid, large-scale propagation can be 

accomplished by in vitro culture techniques using leaf 

petiole sections (40, 83, 165, 281). 

Salpiglossis sinuata. Painted tongue. Semi-hardy 

annual. Seed germination is at 21 to 22°C (70 to 72°F) 

but can be slow and uneven. Can be micropropagated 

(194). 

Salvia spp. Sage (65). Annual, biennial, and perennial 

species. Salvia are used in borders, containers, or as cut 

flowers (16). Seed germination is at 24 to 25°C (75 to 

78°F) and may respond to light (18). Softwood cuttings 

from non-flowering plants root readily under mist 

and may benefit from 1,000 ppm IBA. 

S. greggii. Easily propagated by semi-hardwood 

cuttings (153). Plants can be divided, but such divisions 

are slow to recover. 

S. officinalis. Basal cuttings root better than 

apical cuttings. Flowering reduces rooting and removal 

of flowers enhances propagation. Rooting is enhanced 

with basal dips of 1,000 ppm K-IBA salt (246). 

Rooting ability was highest in spring (Israel). 

S. splendens. Scarlet sage. Tender perennial grown 

as an annual. Germinate seeds at 24 to 25°C (75 to 78°F), 

then grow at 13°C (55°F) night temperature. Seeds 

soaked for 6 days at 6°C (43°F) can promote germination 

(56). Softwood cuttings taken in fall root readily. 

Sandersonia aurantiaca. Climbing, tender, tuberous 

plant with orange flowers like inverted lanterns. 

Grown as a container plant or cut flower. Propagation 

is by division of the tuberous root or by micropropagation 

(114). 

Sanguinaria canadensis. Bloodroot. Ephemeral, 

North American native producing white flowers in 

early spring. Seeds have morphophysiological dormancy 

and require cycles of warm followed by chilling 

stratification. It can take several years to produce a 

seedling. 

Sansevieria trifasciata and S. ‘hahnii’ (Dwarf 

Form). Bowstrip hemp. Snakeplant. Tropical perennial. 

Plants grow from a rhizome, which can be readily 

divided. Leaves may be cut into sections, several inches 

long, and inserted into a rooting medium; a new shoot 

and roots will develop from the base of leaf cutting. 

The variegated form, S. trifasciata ‘Laurentii,’ is a 

chimera, which can be maintained only by division. 

S. trifasciata has been micropropagated (42). 

Santolina chamaecyparissus (incana). Lavender cotton. 

A perennial native to the Mediterranean that is 

used as carpet bedding or a low hedge. Must be 

trimmed to maintain compact growth. Seeds germinate 

at 18 to 21°C (65 to 70°F). It is easily propagated by 

stem cuttings. 

Sanvitalia procumbens. Creeping zinnia. Hardy 

annual. Seed germination is at 20°C (68°F). Plants are 

easily propagated using stem cuttings treated with up 

to 2,500 ppm IBA under mist (99). 

Saponaria ocymoides. Rock soapwort. Hardy 

short-lived perennial used in rock gardens or as a 

bedding plant. Seed germination is at 21°C (70°F) in 

the dark. 

S. pfficinalis. Bouncing Bet. Hardy perennial. 

Seeds germinate at 20°C (68°F). The plant spreads rapidly 

by an underground creeping stem, which can be 

divided. 

Sarracenia spp. Pitcher plant. Perennial carnivorous 

plants native to bog ecosystems. Leaves are modified to 

form spectacular pitchers that entrap insects. Also 

grown for cut foliage for the florist industry. 

Propagation is by division of the rhizome (68). 

Saxifraga spp. Many interesting unusual species and 

hybrids. Tender or hardy perennials. Seeds germinate 

easily at 21°C; they are preferably sown when ripe. 

Seed germination is at 21 to 24°C (70 to 75°F). Some 

hybrids and cultivars are maintained only by vegetative 

methods and are propagated once flowering is finished 

in June or July (England) (269). Cuttings are small and 

slow growing—it takes one year to grow a liner.


Cuttings are rooted in a cold frame or seed tray. Most 

plants grow as small rosettes and are easily propagated 

by making small cuttings involving single rosettes. 

Small plants from stolons root readily. Plants can be 


S. stolonifera. Strawberry geranium. A tender 

perennial grown indoors or as a bedding plant. It can 

be reproduced by removing plantlets from the runners. 

Scabiosa spp. Pincushion flower. Annual and hardy 

perennial garden plants. Seed germination is at 18 to 

21°C (65 to 70°F). Perennial kinds can be divided. 

Scaevola aemula. Fan flower. Tender perennial grown 

for its trailing habit and blue flowers. Most commonly 

used as a hanging basket. Propagation is from stem cuttings 

that are rooted under moderate mist with bottom 

heat at 20 to 22°C (68 to 72°F). Auxin is not required 

but up to 2,500 ppm IBA can be used to improve uniformity 

(99). Micropropagation is possible (38). 

Scarlet Sage. See Salvia splendens. 

Schefflera (synonym Brassaia) arboricola and S. 

actinophylla (137). Umbrella tree. Tropical perennial 

plants used in warm climate landscapes and as an 

important indoor foliage plant. Schefflera is an important 

foliage plant that can be propagated easily by 

seeds, cuttings, or air layering. Basal cuttings develop 

more roots and longer shoots and require less time to 

break lateral buds than do apical cuttings (137). As single-node 

cutting length increased to 20 cm (8 in) so did 

rooting, bud-break, and shoot growth. Seeds germinate 

at 22 to 24°C (72 to 75°F). 

Schizanthus spp. Butterfly flower. Tender annual 

grown as a seasonal pot plant. Seed germination is at 18 

to 22°C (64 to 72°F) in the dark. Seeds are sensitive to 

high temperatures (18). Sow seeds in fall for early 

spring blooms indoors, or sow in early spring to be 

transplanted outdoors for summer blooms. 

Schlumbergera truncata. Christmas cactus. 

Propagation same as Epiphyllum. 

Scilla spp. Squill (92). Includes several kinds of bulbous 

hardy and half-hardy spring-flowering perennials. 

Dig plants when leaves die down in summer and 

remove the bulblets. S. autumnalis is planted in spring 

and blooms in fall. Can be micropropagated (155). 

Scutellaria spp. Skullcap. Annual or herbaceous 

perennials used as bedding plants, in containers or in 

the perennial bed. Seed germination is at 21 to 24°C 

(70 to 75°F) in light. Perennial types can also be 

divided or multiplied by stem cuttings. 


Sedum spp. (269). Sedum is composed of a wide 

range of species including herbaceous perennials, evergreens, 

and monocarps. Many of the Sedum species 

can be raised by seed, but generally this method is limited 

to herbaceous perennials only; seeds germinate at 

15 to 18°C (65°F) in light. S. acre should have alternating 

day [29°C (86°F)] and night [21°C (70°F)]. 

The mat-forming species are propagated by division, 

since the creeping shoots root into the ground as they 

travel and mats are easily pulled apart. Direct sticking 

cuttings into containers is done, since many species 

root so readily. 

Sempervivum. See Succulents. 

Senecio cineraria. Dusty miller (223). Semi-hardy 

perennials usually grown as annuals for their silvery 

foliage. Seeds germinate at 24 to 26°C (75 to 80°F). 

Stem-tip cuttings root rapidly if treated with IBA and 

placed under mist with bottom heat. 

Sidalcea malviflora. Sidalcea (286). A native western 

U.S. perennial used as a border plant. Seeds germinate 

at 18 to 21°C (65 to 70°F). Cultivars are commonly 

propagated by division. 

Silene spp. Catchfly, campion. Annual and shortlived 

perennials grown for bright pink, red, or white 

flowers. Seeds germinate at 18 to 21°C (65 to 70°F). 

Perennial types are divided, or basal stem cuttings can 

be rooted. 

Sinningia speciosa. Gloxinia. Tropical perennial. 

Commonly grown from seeds, which are very fine and 

require light. Sow uncovered, in well-drained peat moss 

medium; they emerge in two weeks at 20°C (68°F). 

Vegetative methods are required to reproduce cultivars. 

Plant grows from a tuber on which a rosette of leaves is 

produced. The root can be divided as described for 

tuberous begonia. Softwood cuttings or leaf cuttings 

taken in spring from young shoots starting from the 

tubers root easily. Gloxinia can also be micropropagated 

using leaf explants (163). 

Snapdragon. See Antirrhinum majus. 

Solanum spp. A diverse group of tender, annual, 

herbaceous, and woody perennials related to potato. 

S. pseudocapsicum (Christmas cherry) is grown as a seasonal 

container plant. It is propagated by seeds, which 

germinate at 18 to 21°C (65 to 70°F) in light. 

S. crispeum and S. kasminoides are vines and 

S. rantonnettii is a woody shrub usually grown as a 

container standard. All are commonly propagated by 

softwood stem cuttings rooted under mist.



Solenostemon scutellarioides. (formerly Coleus 

blumei) (27). Tender perennials. Used for containers 

and as bedding plants. Plants are grown for their wide 

selection colorful foliage. Seeds germinate at 21 to 

24°C (70 to 75°F) in light. Coleus is commonly propagated 

from cuttings that root easily under mist without 

auxin. 

Solidago spp. Goldenrod. Hardy perennial. Grown as 

a cut flower and for the perennial garden. Plants can be 

grown from seeds or division, but are usually propagated 

from stem cuttings. Seeds germinate at 20 to 

22°C (68 to 72°F) and some species benefit from 

10 weeks of chilling stratification (46). Stem cuttings 

are taken from basal vegetative growth in the spring 

and rooted under mist without auxin. Division is from 

dormant plants. 

xSolidaster. An intergeneric hybrid between 

Solidago and Aster that is also grown as a cut flower 

from stem cuttings. Plants can also be divided. 

Spathophyllum spp. Spatheflower. Tropical evergreen 

plants grown in indoor containers or as bedding plants 

in tropical regions. Plants can be propagated by crown 

division or commercially by micropropagation (117). 

Spider plant. See Chlorophytum comosum. 

Spigelia marilandica. Pinkroot. Herbaceous perennial 

with tubular red flowers. Underused perennial due 

to difficulty in propagation. Plants can be multiplied 

by division or stem cuttings. Stem cuttings root under 

mist when taken from greenhouse-grown stock plants 

(118). Plants can also be micropropagated. 

Stachys spp. Lamb’s ear (S. byzantina), big betony (S. 

grandiflora). Hardy perennials used as border plants or 

ground covers. Propagated by clump division or by 

seed. Seed germinates at 21°C (70°F). 

Stapelia spp. Carrion flower. Tender perennial succulent 

that produces large star-shaped flowers that have an 

unpleasant odor, which attracts flies as pollinators. 

Propagated by seeds sown at 21°C (70°F), by division or 

stem cuttings. See Succulents for detailed information. 

Sternbergia lutea. Autumn daffodil. Small fall flowering 

bulb with bright yellow flowers. Propagated by offsets 

of the bulb. 

Stock. See Matthiola. 

Stokesia laevis. Stokes aster. Hardy perennial. Seeds 

germinate at 21 to 24°C (70 to 75°F) and the plants 

bloom the first year. Commonly propagated from root 

cuttings or division. 

Strelitzia reginae. Bird-of-paradise. Tropical perennial 

producing the recognizable bird of paradise flower. 

Grown as a greenhouse ornamental and a cut flower. 

Seed propagation of this tropical perennial is undesirable 

due to juvenility and genetic variation. Seeds germinate 

in 6 to 8 weeks using bottom heat at 37°C 

(98°F) (72). This species grows from a rhizome, which 

can be divided in the spring; however, division is limited 

by a low rate of multiplication with 0.5 to 1.5 divisions 

per branch per year. A technique has been developed 

to overcome the strong apical dominance, which 

inhibits branching of axillary buds into propagules. A 

triangular incision with a knife is made at the base of a 

separated branch 8 to 12 mm above the basal plate to 

reach and remove the apex from adult plants (304). 

After 2 to 6 months, 2 to 30 lateral shoots develop 

from each fan (separated branch). During the next 6 

months, newly formed laterals root and can be divided 

into individual plants (see Chapter 15). 

Streptocarpus xhybridus. Cape primrose is a herbaceous 

perennial in the Gesneriaceae. It is generally 

propagated by seed or leaf cuttings. Seeds germinate at 

21°C (70°F). Seeds are tiny and should not be allowed 

to dry out. Leaf cuttings are made by splitting the leaf 

down the midrib to form two leaf segments. The base 

of the leaf segment is removed and the remaining leaf 

cutting is placed into a peat-lite medium held at 21°C 

(70°F). New plants appear in several months. Cape 

primrose has been successfully micropropagated using 

explants of leaf discs, shoot apices, stem, petiole, pedicel 

segments, and corolla flower parts (230). 

Succulents (28, 106, 234, 282). This loosely defined 

horticultural group includes many genera, such as 

Agave, Aloe, Crassula, Echevaria, Euphorbia, Gasteria, 

Haworthia, Hoya, Kalanchoe, Mesembryanthemum, 

Portulaca, Sedum, Sempervirens, and Yucca. These are 

plants with fleshy stems and leaves that store water, or 

plants that are highly drought-resistant. Most are halfhardy 

or tender perennials. Seed propagation is possible, 

although young plants are often slow to develop 

and to produce flowers. It is best to germinate seeds 

indoors at high day temperatures (29 to 35°C, 85 to 

95°F). Seedlings are susceptible to damping-off. 

Cuttings of most species root readily—either stem, 

leaf-bud, or leaf—in a 1:1 peat-perlite medium. They 

should be exposed to the open air or inserted into dry 

sand for a few days to allow callus to develop over the cut 

end. Some protection from drying is needed during rooting. 

Some species can be reproduced by removing offsets. 

Grafting is possible as described for cacti. Many of the 

succulents can be micropropagated (249, 270, 276, 287).


Sutera spp. Bacopa. Trailing annual mainly grown in 

hanging baskets or mixed containers. Plants are propagated 

from cuttings treated with 2,500 ppm IBA under 

mist with bottom heat at 18 to 20°C (65 to 68°F). 

Overuse of mist can be a problem if rooting substrate 

becomes saturated (99). 

Sweet Alyssum. See Lobularia maritima. 

Sweet Pea. See Lathyrus. 

Symphytum spp. Comfrey. Hardy perennial. Grown 

as an herb or ornamental garden plant. Cultivars are 

propagated mainly from root cuttings or division. 

Micropropagation is from stem explants (140). 

Syngonium podophyllum. Arrowhead vine. Tropical 

perennial vine grown as an indoor foliage plant. Seeds 

germinate at 24 to 27°C (75 to 80°F). Plants also root 

easily from single eye leaf-bud or stem cuttings as well 

as tissue culture. 

Tagetes spp. Marigold (223). Tender annuals. Plants 

are used as bedding plants and cut flowers. Seeds germinate 

readily within 1 week at 21 to 24°C (70 to 

75°F). Can be sown in place in spring after frost in 

mild climates. T. erecta (African marigold) has been 

micropropagated from leaf segments (180). Somatic 

embryos have also been developed (37). 

Tanacetum coccineum (formerly Chrysanthemum 

coccineum). Painted daisy. Hardy perennial for the 

flower border. Can be propagated by seeds that emerge 

in 2 weeks at 16 to 21°C (60 to 70°F). Most often 

propagated by division or basal stem cuttings. 

T. parthenium (formerly Chrysanthemum 

parthenium). Feverfew. Hardy perennial usually grown 

as an annual. Seeds germinate in about 1 week at 20°C 

(68°F) in light. Plants easily self-seed and can be divided. 

T. ptarmiciflorum. Dusty miller. Tender perennial 

grown as an annual. Propagated from seeds that 

emerge within 2 weeks at 22 to 24°C (72 to 75°F) in 

light. 

Teucrium spp. Germander. Herbaceous and woody 

perennials grown mainly for their green or silvery 

foliage. Often pruned into garden borders or used in 

knot gardens. Seeds germinate at 18 to 21°C (65 to 

70°F). Commonly propagated by stem cuttings using 

mist or high humidity with bottom heat. 

Thalictrum spp. Meadow rue. Hardy perennial. Seeds 

germinate at 20°C (68°F). May benefit from 

1 week of chilling stratification. Plants can be multiplied 

by dormant divisions in spring or fall. 


Thermopsis caroliniana. Hardy perennial. Seeds have 

hard seed coats and require scarification. Seeds germinate 

at 21°C (70°F). Plants can be divided, but it is best 

to leave them undisturbed for garden performance. 

Thunbergia spp. Clockvine. Tender annual and 

perennial vines. T. alata (black-eyed Susan) and T. gregorii 

are grown as summer annuals on a garden support 

or as a ground cover. T. grandiflora (Blue trumpet vine) 

and T. mysorensis are usually used as perennial vines in 

greenhouse displays for spring or fall blooms. Seeds 

germinate at 21 to 24°C (70 to 75°F), but seedlings 

grow slowly. Softwood cuttings taken from new shoots 

root readily with bottom heat. 

Thymus spp. Thyme. Hardy creeping perennials grown 

as ground covers for small spaces or in containers. 

Leaves are fragrant. Seeds germinate at 21°C (70°F). 

Germination may be promoted by light. Can also be 

increased by division or by softwood cuttings taken in 

summer. Plants have been micropropagated (121). 

Ti. See Cordyline terminalis. 

Tiarella cordifolia. Foamflower. Hardy perennial 

grown as a ground cover in the shade. Can be propagated 

from seed or division. Seeds emerge within 

2 weeks at 18°C (65°F). Tiarella is commercially 

micropropagated from shoot explants (175). 

Tigridia pavonia. Tiger flower (92). Tender bulbous 

perennials. Plant bulbs in spring and dig in fall when 

leaves die. Increase by removal of small bulblets. Easily 

started by seed. 

Tillandsia spp. See Bromeliads. 

Tithonia rotundifolia. Mexican sunflower. Tender 

perennial with large composite flowers grown as an 

annual. Seeds germinate at 21°C (70°F). 

Tolmiea menziesii. Piggyback plant. Tender perennial 

used as an indoor foliage plant. New plantlets form on 

upper surface of leaves. Plantlets can be removed and 

rooted. Also propagated from stem (rhizome) cuttings. 

Torenia fournieri. Wishbone flower (272). Torenia is a 

tender perennial grown as an annual for semi-shady garden 

areas. Seed germination is at 21 to 23°C (70 to 75°F) 

with light. Plants are also propagated from terminal cuttings 

treated with 2,500 ppm IBA under mist (99). 

Trachymene coerulea. Laceflower. Tender perennial 

grown as an annual for display or cut flowers. Seeds 

germinate at 20°C (68°F). 

Tradescantia spp. Spiderwort. Hardy perennial 

grown for their foliage color or their long-blooming 

blue, pink, or white flowers held above grass-like



foliage. Seeds germinate at 21°C (70°F). Cultivars are 

propagated from dormant divisions in spring or 

autumn. Stem cuttings root easily under mist or high 

humidity without auxin. 

Tricyrtis spp. Toad lily. Hardy perennial. Unique flowers 

produced in the early autumn. Plants prefer shade. 

Propagation is from seed, division, or stem cuttings. 

Seeds require stratification. Tricyrtis has become widely 

available partly due to its ease of micropropagation. 

Trillum spp. Trillum, wake robin. Hardy herbaceous 

perennials grown in the woodland garden. Plants produce 

white, yellow, or red flowers with three pigmented 

petals. Seeds are covered with an aril called an elaisome 

that attracts ants, which disseminate the seed. Seeds 

should be sown as soon as the seed ripens. Maintain 

even moisture levels until seedlings emerge. Seeds have 

morphophysiological dormancy where the radicle 

emerges after the first chilling stratification and the epicotyl 

emerges after a second chilling stratification, 

which means two seasons are required for seedling 

emergence (49, 273). Many trillium produce shoots 

from rhizomes. The rhizome can be notched behind the 

apical shoot bud to induce numerous new buds near the 

wound site. After 1 year, these new shoots can be separated, 

including a piece of the rhizome (41). Some trillium 

species have been micropropagated (232). 

Trollius spp. Globeflower. Hardy perennial grown for 

their striking orange-yellow flowers. Seeds show 

endogenous dormancy and should be stratified or 

planted in fall to produce plants that flower by next 

spring (49). Plants are also increased by crown division. 

Tropaeolum majus. Nasturtium. Tender perennial 

grown as an annual. Seeds germinate at 18 to 21°C (65 

to 70°F). Plants can be difficult to transplant and are 

often seeded in place. Double-flowering kinds must be 

propagated vegetatively, usually by softwood cuttings. 

Tulipa spp. and Hybrid Cultivars. Tulip (192). 

Hardy perennials from tunicate bulbs. Tulips are used 

for seasonal bedding plants, pot plants, and cut flowers. 

Plant bulbs in fall for spring blooms. Seeds are used to 

reproduce species and for breeding new cultivars. They 

germinate readily after chilling stratification. Vegetative 

methods include removal of offset bulbs in the fall. 

Different bulb sizes are planted separately, since the 

time required to produce flowers varies with size. For 

details of procedure, see Chapter 15. Tissue culture of 

tulip is possible but results are variable and success rates 

are low. Additional work is needed to develop a commercial 

micropropagation system (4). 

Tweedia caerulem. (synonym Oxypetalum). Hardy 

perennial grown for its pale blue flowers that make 

long-lasting cut flowers. Seeds germinate within 

2 weeks at 21°C (70°F) in light. 

Valeriana. See Centranthus. 

Verbascum spp. Mullein. Hardy perennials and biennials 

grown for their showy spikes of flowers. Seeds germinate 

at 18 to 21°C (65 to 70°F). Propagate named 

cultivars by root cuttings taken in early spring before 

vegetative growth begins. 

Verbena spp. Verbena. Tender perennials grown as an 

annual. Seeds germinate at 24 to 27°C (75 to 80°F), 

but germination can be erratic (65). Seeds are sensitive 

to overwatering (60). Hardy kinds can be propagated 

by division or from softwood cuttings taken in summer. 

Stem cuttings are treated with 1,000 ppm IBA 

and rooted under mist (99). 

Veronica spp. Speedwell. Diverse group of hardy 

perennials producing white or blue flowers on upright 

or spreading plants depending on the species. Seeds 

germinate at 18 to 24°C (65 to 75°F) with light. Plants 

are increased by division in spring or fall or by softwood 

cuttings taken in the spring or summer. Plants 

can be micropropagated (280). 

Vinca. See Catharanthus. 

Vinca major. Tender perennial grown as a ground 

cover. Propagated by division or by softwood cuttings 

treated with 1,000 ppm IBA under mist (99). 

V. minor. Periwinkle. Hardy perennial. Seeds 

germinate at 20°C (68°F). Easily propagated by softwood 

cuttings or by division. V. minor can also be 


Viola spp. Violets. Many hardy perennial kinds. 

Species violets can be propagated by seeds, but germination 

may be slow and seeds are best exposed to chilling 

stratification before planting. Many species produce 

seeds in inconspicuous, enclosed (cleistogamous) flowers 

near the ground, whereas the conspicuous, showy 

flowers produce few or no seeds. These plants can also 

be reproduced by cuttings or by division (80). 

Viola cornuta. Horned violet, tufted pansy. 

Hardy perennial. Seeds germinate at 18 to 21°C (65 to 

70°F). Seeds of some cultivars need light. Vegetative 

propagation is by cuttings taken from new shoots 

obtained by heavy cutting back in the fall. Clumps may 

also be divided.


V. odorata. Sweet violet. Tender to semi-hardy 

perennials. Grows by rhizome-like stems, which can be 

separated from others on the crown and treated as a 

cutting with some roots present. 

V. tricolor. Johnny-jump-up. Hardy or semihardy, 

short-lived perennial. Usually propagated by 

seeds as described for V. cornuta but may also be 

increased by division. 

Viola xwittrockiana. Pansy. Short-lived perennial 

grown as an annual. Popular as an autumn and 

early spring bedding plant. Propagation is by seed. 

Seeds germinate at 18 to 21°C (65 to 70°F) with light. 

Pansy seed experiences thermoinhibition at temperatures 

above 30°C (86°F) and fails to germinate. These 

temperatures are common in summer greenhouses 

when pansy seed is normally sown, but seed priming 

alleviates this problem (58). Pansy seed is commonly 

sold as primed seed from the seed company. 

Vriesea. See Bromeliads. 

Yucca spp. Yucca. Tender to semi-hardy perennials. 

Seeds germinate at 20°C (68°F) but require several 

years to flower. Plants are monocots; some are essentially 

stemless and grow as a rosette, while others have 

either long or short stems. Offsets growing from the 

REFERENCES 

1. Adams, R. M., S. S. Koenigsberg, and R. W. 

Langhans. 1979. In vitro propagation of Cephalotus follicularis 

(Australian pitcher plant). HortScience 14:512–13. 

2. Aelbrecht, J. 1989. The effect of different 

treatments on the germination of Lewisia hybrid seeds. 

Acta Hort. 252:239–45. 

3. Albers, M. R. J., and B. P. A. M. Kunneman. 

1992. Micropropagation of Paeonia. Acta Hort. 

314:85–92. 

4. Alderson, P. G., and A. G. Taeb. 1990. Influence 

of culture environment on shoot growth and bulbing of 

tulip in vitro. Acta Hort. 266:91–4. 

5. Allen, P. S., and S. E. Meyer. 1990. Temperature 

requirements of three Penstemon species. HortScience 

25:191–93. 

6. Al-Matar, M., J. M. Al-Khayri, M. S. Brar, 

and G. L. Klingaman. 1999. In vitro regeneration of 

long spur barrenwort (Epimedium grandiflorum Morr.) 

from rachis explants. In Vitro Cell. Dev.—Plant 

35:245–48. 


base of the plant can be removed and handled as cuttings; 

sometimes entire branches or the top of the plant 

can be detached a few inches below the place where 

leaves are borne and replanted in sandy soil. Sections of 

old stems can be laid on sand or other medium in a 

warm greenhouse, and new side shoots that develop 

can be detached and rooted. Y. elephantipes is rooted by 

long canes (239). 

Zantedeschia spp. Calla (120). Tropical perennials 

used as cut flowers and seasonal pot plants. Plants are 

propagated by seed, division, and tissue culture. Plants 

grow by thickened rhizomes (or tuber) that produce 

offsets or rooted side shoots; these are removed and 

planted. Calla are also commercially micropropagated 

(79, 160). 

Zebrina pendula. Wandering Jew. Tender perennial. 

Easily propagated at any season by stem cuttings. 

Zephyranthes spp. Zephyr lily (92). Tender perennial 

produced from a bulb. Used as a seasonal pot plant or 

annual display. Multiplied by offsets of the bulb. 

Zinnia elegans and other species. Zinnia (223). 

Half-hardy hot-weather annuals used as bedding plants 

or cut flowers. Greenhouse germination is rapid 

(within 1 week) for seeds sown at 21°C (70°F). 

7. Amaki, A., and H. Higuchi. 1992. 

Micropagation of Boston ferns (Nephrolepsis spp.). In Y. 

P. S. Bajaj, ed. Biotechnology in Agriculture and Forestry. 

Vol. 20. High-tech and micropropagation IV. Berlin: 

Springer-Verlag. pp. 484–94. 

8. Anderson, R. A., R. L. Geneve, and L. Utami. 

1991. Gotta cut godetia. Greenhouse Grower 9(1):46–8. 

9. Anthony, J. L. 1992. In vitro propagation of 

Drosera spp. HortScience 27:850. 

10. Apps, D. A., and C. W. Heuser. 1975. 

Vegetative propagation of Hemerocallis—including tissue 

culture. Comb. Proc. Intl. Plant Prop. Soc. 25:362–67. 

11. Arditti, J. 1967. Factors affecting the germination 

of orchid seeds. Bot. Rev. 33:1–97. 

12. Arditti, J. 1977. Orchid biology. Ithaca, NY: 

Cornell Univ. Press. 

13. Arditti, J. 1982. Orchid seed germination 

and seedling culture—a manual. In J. Arditti, ed. 

Orchid biology: Reviews and perspectives II. London: 

Cornell Univ. Press. pp. 242–370.



14. Arditti, J, and R. Ernst. 1993. 

Micropropagation of orchids. New York: John Wiley. 

15. Armitage, A. M. 1986. Seed propagated geraniums. 

Portland OR: Timber Press. 

16. Armitage, A. M. 1987. The influence of spacing 

on field grown perennial crops. HortScience 22:904–7. 

17. Arteca, R. N., D. S. Tsai, and C. 

Schiangnhauler. 1985. Abscisic acid effects on photosynthesis 

and transpiration in geranium cuttings. 

HortScience 20:370–72. 

18. Assn. Off. Seed Anal. 1993. Rules for seed 

testing. J. Seed Tech. 16:1–113. 

19. Ault, J. R. 1995. In vitro propagation of 

Eucomis autumnalis, E. comosa and E. zambesiaca by 

twin scaling. HortScience 30:1441–42. 

20. Ault, J. R., and W. J. Blackmon. 1987. In 

vitro propagation of Ferocactus acanthodes (Cactaceac). 


21. Ault, J. R., and K. Havens. 1999. 

Micropropagation of Baptisia ‘Purple Smoke.’ 


22. Bach, A. 1987. The capability of in vitro 

regeneration of various cultivars of Freesia hybrida. Acta 

Hort. 212:715–18. 

23. Bach, A. 1992. Micropagation of Hyacinths 

(Hyacinthus orientalis L.). In Y. P. S. Bajaj, ed. 

Biotechnology in agriculture and forestry. Vol. 20. Hightech 

and micropropagation IV. Berlin: Springer-Verlag. 

pp. 144–59. 

24. Bailey, L. H., E. Z. Bailey, and Staff of 

Bailey Hortorium. 1976. Hortus third. New York: 

Macmillan. 

25. Bajaj, Y. P. S., M. M. S. Sidhu, and A. P. S. 

Gill. 1992. Micropagation of Gladiolus. In Y. P. S. 

Bajaj, ed. Biotechnology in agriculture and forestry. Vol. 

20. High-tech and micropropagation IV. Berlin: 


26. Bajaj, Y. P. S. 1992. Micropagation of 

Chrysanthemum. In Y. P. S. Bajaj, ed. Biotechnology in 

agriculture and Forestry. Vol. 20. High-tech and micropropagation 

IV. Berlin: Springer-Verlag. pp. 69–80. 

27. Ball, V., ed. 1991. The Ball red book: 

Greenhouse growing. 15th ed. Reston, VA: Reston Publ. 

28. Bayer, M. B. 1982. The new Haworthia 

handbook. Pretoria: National Botanic Gardens of South 

Africa. 

29. Beattie, D. J. 1993. Propagation of Astilbe. 

Comb. Proc. Intl. Plant Prop. Soc. 43:509–10. 

30. Beattie, D. J., and J. W. White. 1993. 

Lilium—hybrids and species. In A. De Hertogh and 

M. Le Nard, eds. The physiology of flowering bulbs. 

Amsterdam: Elsevier. pp. 423–54. 

31. Bech, K., and K. Husted. 1996. Verification 

of ELISA as a reliable test method for kalanchoe mosaic 

potyvirus (KMV) and establishment of virus-free 

Kalanchoe blossfeldiana by meristem-tip culture. Acta 

Hort. 432:298–305. 

32. Beebee, J. D. 1980. Morphogenetic response 

of seedlings and adventitious buds of the carnivorous 

plant Dionaea muscipula to aseptic culture. Bot. Gaz. 

141:396–400. 

33. Benschop, M. 1993. Crocus. In A. De 

Hertogh and M. Le Nard, eds. The physiology of flowering 

bulbs. Amsterdam: Elsevier. pp. 257–72. 

34. Benschop, M. 1993. Polianthes. In A. De 



35. Benson, E. E., J. E. Danaher, I. M. Pimbley, 

C. T. Anderson, J. E. Wake, S. Daley, and L. K. Adams. 

2000. In vitro micropropagation of Primula scotica: A 

rare Scottish plant. Biodivers. Conserv. 9:711–26. 

36. Besemer, S. 1980. Carnations. In R. A. 

Larson, ed. Introduction to floriculture. New York: 

Academic Press. 

37. Bespalhok, E., and K. Hattori. 1998. Friable 

embryogenic callus and somatic embryo formation 

from cotyledon explants of African marigold (Tagetes 

erecta L.). Plant Cell Rept. 17:870–75. 

38. Bhalla, P. L., and K. Sweeney. 1999. Direct 

in vitro regeneration of the Australian fan flower, 

Scaevola aemula R. Br. Scientia Hort. 79:65–74. 

39. Bicknell, R. A. 1984. Seed propagation of 

Gentiana scabra. Comb. Proc. Intl. Plant Prop. Soc. 

34:396–401. 

40. Bilkey, P. C., B. H. McCown, and A. C. 

Hildebrandt. 1978. Micropropagation of African violet 

from petiole cross-sections. HortScience 13:37–8. 

41. Blanchette, L. 1998. Asexual propagation of 

Anemonella, Dodecatheon, and Trillium. Comb. Proc. 

Intl. Plant Prop. Soc. 48:327–29. 

42. Blazich, F. A., and R. T. Novitzky. 1984. In 

vitro propagation of Sansevieria trifasciata. HortScience 

19:122–23. 

43. Borowski, E., P. Hagen, and R. Moe. 1981. 

Stock plant irradiation and rooting of chrysanthemum 

cuttings in light or dark. Scientia Hort. 15:245–53. 

44. Bose, T. K., B. K. Jana, and S. Moulilk. 

1987. A note on the micropropagation of tuberose 

from scale stem section. Indian J. Hort. 44:100–1. 

45. Bouza, L., M. Jacques, and E. Miginiac. 

1994. In vitro propagation of Paeonia suffruticosa 

Andr. cv. ‘Mme. De Vatry’: Developmental effects of 

exogenous hormones during the multiplication phase. 

Scientia Hort. 57:241–51.


46. Bratcher, C. B., J. M. Dole, and J. C. Cole. 

1993. Stratification improves seed germination of five 

native wildflower species. HortScience 28:899–901. 

47. Bridgen, M. P., J. J. King, C. Pedersen, M. A. 

Smith, and P. J. Winski. 1992. Micropropagation of 

Alstroemeria hybrids. Comb. Proc. Intl. Plant Prop. Soc. 

42:427–30. 

48. Bridgen, M. P., and J. Todd. 1998. Genotypic 

and environmental effects on root cutting propagation 

of Pulmonaria species and cultivars. Comb. Proc. Intl. 

Plant Prop. Soc. 48:319–23. 

49. Brumback, W. E. 1985. Propagation of wildflowers. 


50. Buchheim, J. A. T., and M. M. Meyer, Jr. 

1992. Micropropagation of peony (Paeonia spp.). In Y. 

P. S. Bajaj, ed. Biotechnology in agriculture and forestry. 



51. Burr, R. W. 1975. Mass production of 

Boston fern through tissue culture. Comb. Proc. Intl. 


52. Burrell, C. C. 2006. Hellebores: a comprehensive 

guide. Portland, OR: Timber Press. 

53. Bush, S. R., E. D. Earle, and R. W. Langhans. 

1976. Plantlets from petal segments, petal epidermis, 

and shoot tips of the periclinal chimera, Chrysanthemum 

morifolium ‘Indianapolis,’ Amer. J. Bot. 63:729–37. 

54. Butcher, S. M., R. A. Bicknell, J. F. Seelye, and 

N. K. Borst. 1986. Propagation of Limonium peregrinum. 


55. Calvo, M. C., and J. Segura. 1989. In vitro 

propagation of lavender. HortScience 24:375–76. 

56. Carpenter, W. J. 1989. Salvia splendens seed 

pregermination and priming for rapid and uniform 

plant emergence. J. Amer. Soc. Hort. Sci. 114:247–50. 

57. Carpenter, W. J. 1990. Light and temperature 

govern germination and storage of Caladium seed. 


58. Carpenter, W. J., and J. F. Boucher. 1991. 

Priming improves high-temperature germination of 

pansy seed. HortScience 26:541–44. 

59. Carpenter, W. J., and J. F. Boucher. 1992. 

Temperature requirements and germination of 

Delphinium cultorum seed. HortScience 27:989–92. 

60. Carpenter, W. J., and S. Maekawm. 1991. 

Substrate moisture level governs the germination of 

verbena seed. HortScience 26:1468–72. 

61. Carpenter, W. J., and E. R. Ostmark. 1992. 

Growth regulator and storage temperature govern germination 

of Coreopsis seed. HortScience 27:1190–93. 

62. Carpenter, W. J., E. R. Ostmark, and J. A. 

Cornell. 1993. The role of light during Phlox 


drummondii Hook. seed germination. HortScience 

28:786–88. 


Cornell. 1994. Light governs the germination of 

Impatiens wallerana Hook. f. seed. HortScience 

29:854–57. 


Cornell. 1995. Temperature and seed moisture govern 

germination and storage of Gerbera seed. HortScience 

30:98–101. 

65. Carpenter, W. J., and S. W. Williams. 1993. 

Keys to successful seeding. Grower Talks 57:34–44. 

66. Carter, F. M. 1973. Grafting cacti. 

Horticulture 51:34–5. 

67. Cassells, A. C. 1992. Micropropagation of 

commercial Pelargonium species and hybrids. In Y. P. S. 

Bajaj, ed. Biotechnology in Agriculture and Forestry: Vol. 

20. High-tech and micropropagation IV. Berlin: 


68. Cheers, G. 1992. Lett’s guide to carnivorous 

plants of the world. London: Charles Lett and Co. 

69. Chen, W. L. 2007. Elimination of in vitro 

contamination, shoot multiplication, and ex vitro rooting 

of Aglaonema. HortScience 42:629–32. 

70. Chidamian, C. 1984. Book of cacti and other 

succulents. Portland, OR: Timber Press. 

71. Choffe, K. L., J. M. R. Victor, S. J. Murch, 

and P. K. Saxena. 2000. In vitro regeneration of 

Echinacea purpurea L.: Direct somatic embryogenesis 

and indirect shoot organogenesis in petiole culture. In 

Vitro Cell. Dev. Biol.—Plant 36:30–6. 

72. Chopping, N. 1986. Replacing the bird: 

Pollination in the genus Strelitzia. Comb. Proc. Intl. 


73. Christie, C. B. 1985. Propagation of amaryllids: 

A brief review. Comb. Proc. Intl. Plant Prop. Soc. 

35:351–57. 

74. Chua, B. U., J. T. Kunisaki, and Y. Sagawa. 

1981. In vitro propagation of Dracaena marginata 

‘Tricolor.’ HortScience 16:494. 

75. Cialone, J. 1984. Developments in Dracaenaproduction. 


76. Clayton, P. Q., J. F. Hubstenberger, and G. 

C. Phillips. 1990. Micropropagation of members of the 

Cactaceae subtribe Cactinae. J. Amer. Soc. Hort. Sci. 

115:337–43. 

77. Cockrel, A. D., G. L. McDaniel, and E. T. 

Graham. 1986. In vitro propagation of florist’s 

cineraria. HortScience 21:139–40. 

78. Cohat, J. 1993. Gladiolus. In A. De Hertogh 

and M. Le Nard, eds. The physiology of flowering bulbs. 

Elsevier, Amsterdam. pp. 297–320.



79. Cohen, D. 1981. Micropropagation of 

Zantedeschia hybrids. Comb. Proc. Intl. Plant Prop. Soc. 

31:312–16. 

80. Colborn, L. N. 1986. Primroses and violets: 

What’s new. Comb. Proc. Intl. Plant Prop. Soc. 36:245–49. 

81. Connor, D. M. 1985. Plants for the discriminating 

propagator. Comb. Proc. Intl. Plant Prop. Soc. 

35:274–77. 

82. Conover, C. A., and R. T. Poole. 1978. 

Production of Ficus elastica ‘Decora’ standards. 


83. Cooke, R. C. 1977. Tissue culture propagation 

of African violets. HortScience 12:549. 

84. Cramer, C. S., and M. P. Bridgen. 1997. 

Somatic embryogenesis and shoot proliferation of 

Mussaenda cultivars. Plant Cell Tissue Org. Cult. 

50:135–38. 

85. Criley, R. A. 1988. Propagation of tropical 

cut flowers: Strelitzia, Alpinia, and Heliconia. Acta 

Hort. 226:509–17. 

86. Custers, J. B. M., and J. H. W. Bergervoet. 

1992. Differences between Nerine hybrids in micropropagation 

potential. Scientia Hort. 52:247–56. 

87. Darrow, G. M., and F. G. Meyer, eds. 1968. 

Day lily handbook. American Horticultural Society, Vol. 

47, No. 2. 

88. Davies, F. T., Jr., and B. C. Moser. 1980. 

Stimulation of bud and shoot development of Rieger 

begonia leaf cuttings with cytokinins. J. Amer. Soc. 

Hort. Sci. 105:27–30. 

89. Davis, T. D., D. Sankhla, N. Sankhla, A. 

Upadhyaya, J. M. Parsons, and S. W. George. 1998. 

Improving seed germination of Aquilegia chrysantha by 

temperature manipulation. HortScience 28:798–99. 

90. Debergh, P. 1976. An in vitro technique for 

the vegetative multiplication of chimaeral plants of 

Dracaena and Cordyline. Acta Hort. 64:17–9. 

91. Debergh, P., and J. DeWall. 1977. Mass 

propagation of Ficus lyrata. Acta Hort. 78:361–64. 

92. De Hertogh, A., and M. Le Nard. 1993. The 

physiology of flowering bulbs. Amsterdam: Elsevier. 

93. De Hertogh, A., and M. Le Nard. 1993. 

Dahlia. In A. De Hertogh and M. Le Nard, eds. The physiology 

of flowering bulbs. Amsterdam: Elsevier. pp. 

273–84. 

94. De Hertogh, A., and K. Zimmer. 1993. Allium. 

In A. De Hertogh and M. Le Nard, eds. The physiology of 

flowering bulbs. Amsterdam: Elsevier. pp. 187–200. 

95. De Bruyn, M. H., D. I. Ferreira, M. M. 

Slabbert, and J. Pretorius. 1992. In vitro propagation of 

Amaryllis belladonna. Plant Cell Tiss. Organ Cult. 

31:179–84. 

96. De Munk, W. J., and J. Schipper. 1993. Iris— 

bulbous and rhizomatous. In A. De Hertogh and M. Le 

Nard, eds. The physiology of flowering bulbs. Amsterdam: 

Elsevier. pp. 349–80. 

97. Desilets, H. 1985. Propagation of herbaceous 

perennials by root cuttings. Comb. Proc. Intl. 


98. Desilets, H., Y. Desjardins, and R. B. 

Belanger. 1993. Clonal propagation of Pelargonium 

hortorum through tissue culture: Effects of salt dilution 

and growth regulator concentration. Can. J. Plant Sci. 

73:871–78. 

99. Dole, J. M., and J. L. Gibson. 2006. Cutting 

propagation. A guide to propagating and producing floriculture 

crops. Batavia, IL: Ball Pub. 

100. Dole, J. M., and H. F. Wilkins. 1999. 

Floriculture: Principles and species. Upper Saddle River, 

NJ: Prentice Hall. 

101. Druge, U., S. Zerche, R. Kadner, and M. 

Ernst. 2000. Relation between nitrogen status, carbohydrate 

distribution and subsequent rooting of chrysanthemum 

cuttings as affected by pre-harvest nitrogen supply 

and cold-storage. Ann. Bot. 85:687–701. 

102. Dubois, J. B., F. A. Blazich, S. L. Warren, 

and B. Goldfarb. 2000. Propagation of Anemone xhybrida 

by root cuttings. J. Environ. Hort. 18:79–83 

103. Dunston, S., and E. Sutter. 1984. In vitro 

propagation of prayer plants. HortScience 19:511–12. 

104. Earle, E. D., and R. W. Langhans. 1975. 

Carnation propagation from shoot tips cultured in liquid 

medium. HortScience 10:608–10. 

105. Ecker, R., and A. Barzilay. 1993. 

Propagation of Asclepias tuberosa from short root segments. 

Scientia Hort. 56:171–74. 

106. Edinger, P., ed. 1970. Succulents and cactus. 

Menlo Park, CA: Lane. 

107. Erickson, D. M. 1985. Propagating and 

growing primroses in the Pacific Northwest. Comb. 

Proc. Intl. Plant Prop. Soc. 35:219–21. 

108. Evenor, D. 2001. Micropropagation of 

Achemilla mollis. Plant Cell Tiss. Organ Cul. 65:169–72. 

109. Evenor, D. and M. Reuveni. 2004. Micropropagation 

of Achillea filipendulina cv. Parker. Plant 

Cell Tiss. Organ Cult. 79:91–3. 

110. Fagan, A. E., M. A. Dirr, and F. A. Pokorny. 

1981. Effects of depulping, stratification, and growth 

regulators on seed germination of Liriope muscari. 


111. Fakhrai, F., and P. K. Evans. 1989. 

Morphogenetic potential of cultured explants of Crocus 

chrysanthus Herbert cv. E. P. Bowles. J. Exp. Bot. 

40:809–12.


112. Farina, E., and B. Ruffoni. 1993. The effect 

of temperature regimes on micropropagation efficiency 

and field performance of Eustoma grandiflorum. Acta 

Hort. 387:73–80. 

113. Fay, A. M., M. A. Bennett, and S. M. Still. 

1994. Osmotic seed priming of Rudbeckia fulgida 

improves germination and expands germination range. 


114. Finne, J. F., and J. Van Staden. 1989. In 

vitro propagation of Sandersonia and Gloriosa. Plant 


115. Finne, J. F., and J. van Staden. 1995. In vitro 

culture of Clivia miniata. In Kim, K. W. and A. A. de 

Hertogh. 1997. Tissue culture of ornamental flowering 

bulbs (geophytes). Hort. Rev. 18:87–169. 

116. Finnerty, T. L., J. M. Zajicek, and M. A. 

Hussey. 1992. Use of seed priming to bypass stratification 

requirements of three Aquilegia species. 


117. Fonnesbech, M., and A. Fonnesbech. 1979. 

In vitro propagation of Spathiphyllum. Scientia Hort. 

10:21–5. 

118. Foster, S., and S. L. Kitto. 2000. Vegetative 

propagation of Spigelia marilandica (Indian pinks) 

from shoot-tip cuttings. HortScience 35:447–48. 

119. Frett, J. J., and M. A. Dirr. 1983. Tissue 

culture propagation of Liriope muscari and Ophiopogon 

jaburan. HortScience 18:431–32. 

120. Funnell, K. A. 1993. Zantedeschia. In A. De 



121. Furmanowa, M., and O. Olszowska. 1991. 

Micropropagation of thyme (Thymus vulgaris L.). In Y. 

P. S. Bajaj, ed. Biotechnology in agriculture and forestry. 



122. Furmanowa, M., and L. Rapczewska. 1993. 

Bergenia crassifolia (L.) Fritsch (Bergenia): Micropropagation 

and arbutin contents. In Y. P. S. Bajaj, ed. 

Biotechnology in agriculture and forestry. Vol. 21. Medicinal 

and aromatic plants IV. Berlin: Springer-Verlag. pp. 18–33. 

123. Garner, J. M., G. J. Keever, D. J. Eakes, and 

J. R. Kessler. Benzyladenine-induced offset formation 

in Hosta dependent of cultivar. Comb. Proc. Intl. Plant 

Prop. 42:605–10. 

124. Gawel, N. J., C. D. Robacker, and W. L. 

Corley. 1990. In vitro propagation of Miscanthus sinensis. 


125. Geneve, R. L. 1999. Seed dormancy in vegetable 

and flower seeds. J. Seed Technol. 20:236–50. 

126. Gertsson, U. E. 1992. Micropropagation of 

cineraria (Senecio hybridus Hyl.). In Y. P. S. Bajaj, ed. 




pp. 396–406. 

127. Gilbertson-Ferriss, T. L., and H. F. Wilkins. 

1977. Factors influencing seed germination of Freesia 

refracta Klatt cv. Royal Mix. HortScience 12:572–73. 

128. Gill, L. M. 1984. Anemone tuber production 

in southwest England. Comb. Proc. Intl. Plant 

Prop. Soc. 34:290–94. 

129. Girija, S., A. Ganapathi, and G. Vengadesan. 

1999. Micropropagation of Crossandra infundibuliformis 

(L.) Nees. Scientia Hort. 82:331–37. 

130. Haegeman, J. 1993. Begonia—Tuberous 

hybrids. In A. De Hertogh and M. Le Nard, eds. The 


pp. 227–38. 

131. Hammer, P. A. 1976. Stolon formation in 

Chlorophytum. HortScience 11:570–72. 

132. Han, B. H., J. S. Kim, S. L. Choi, and K. Y. 

Paek. 1991. In vitro mass propagation of Begonia rex 

Putx. and Caladium bicolor Vent. Korean J. Plant Tissue 

Cult. 18:95–101. 

133. Han, S. S. 1993. Chilling, ethephon and 

photoperiod affect cormel production of Brodiaea. 


134. Han, S. S., and A. H. Halevy. 1993. Triteleia. 

In A. De Hertogh and M. Le Nard, eds. The physiology of 

flowering bulbs. Amsterdam: Elsevier. pp. 611–16. 

135. Hanks, G. R. 1993. Narcissus. In A. De 



136. Hanks, G. R., and A. R. Rees. 1979. Twinscale 

propagation of Narcissus. A review. Scientia Hort. 

10:1–14. 

137. Hansen, J. 1986. Influence of cutting position 

and stem length on rooting of leaf-bud cuttings of 

Schefflera arboricola. Scientia Hort. 28:177–86. 

138. Harazy, A., B. Leshem, A. Cohen, and H. 

D. Rabinowitch. 1985. In vitro propagation of statice 

as an aid to breeding. HortScience 20:361–62. 

139. Harbage, J. F. 2001. Micropropagation of 

Echinacea angustifolia, E. pallida, and E. purpurea from 

stem and seed explants. HortScience 36:360–64. 

140. Harris, P. J. C., C. G. Grove, and A. J. 

Harvard. 1989. In vitro propagation of Symphytum 

species. Scientia Hort. 40:275–81. 

141. Hayashi, T., K. Oshida, and K. Sano. 1988. 

Formation of alkaloids in suspension cultured 

Colchicum autumnale. Phytochemistry 27:1371–74. 

142. Henny, R. J. 1978. In vitro propagation of 

Peperomia ‘Red Ripple’ from leaf discs. HortScience 

13:150–51.



143. Higaki, T., and D. P. Watson. 1973. 

Anthurium culture in Hawaii. Univ. Hawaii Coop. Ext. 

Ser. Circ. 420. 

144. Holley, W. D., and R. Baker. 1963. 

Carnation production. Dubuque, Iowa: William C. 

Brown Co., Publishers. 

145. Homes, J., M. Legeos, and M. Jaziri. 1987. 

In vitro multiplication of C. sativus L. Acta Hort. 

212:675–76. 

146. Hook, I. L. I. 1993. Leontopodium alpinuin 

Cass. (edelweiss): In vitro culture, micropropagation, 

and the production of secondary metabolites. In 

Y. P. S. Bajaj, ed. Biotechnology in agriculture and forestry. 

Vol. 21. Medicinal and aromatic plants IV. Berlin: 


147. Hosokawa, K., Y. Oikawa, and S. 

Yamamura. 1998. Mass propagation of ornamental 

gentian in liquid medium. Plant Cell Rept. 17:747–51. 

148. Hosoki, T., and T. Asahira. 1980. In vitro 

propagation of bromeliads in liquid culture. 


149. Hosoki, T., and D. Kimura. 1997. Micropropagation 

of Centauria macrocephala Pushk. ex 

Willd. by shoot-axis splitting. HortScience 32:1124–25. 

150. Houghton, W. J. 1984. New narcissus and 

their propagation. Comb. Proc. Intl. Plant Prop. Soc. 

34:294–96. 

151. Huang, C. W., H. Okubo, and S. Uemoto. 

1990. Comparison of bulblet formation from twin 

scales and single scales on Hippeastrum hybridum cultured 

in vitro. Scientia Hort. 46:151–60. 

152. Huang, F. H., G. L. Klingaman, and H. H. 

Chen. 1992. Micropropagation of surprise lily (Lycoris 

squamigera). In Y. P. S. Bajaj, ed. Biotechnology in agriculture 

and forestry Vol. 20. High-tech and micropropagation 


153. Hubbard, A. C. 1986. Native ornamentals 

for the U. S. southwest. Comb. Proc. Intl. Plant Prop. 

Soc. 36:347–50. 

154. Hubstenberger, J. F., P. W. Clayton, and 

G. C. Phillips. 1992. Micropropagation of cacti 

(Cactaceae). In Y. P. S. Bajaj, ed. Biotechnology in agriculture 

and forestry. Vol. 20. High-tech and micropropagation 


155. Hussey, G. 1975. Totipotency in tissue 

explants and callus of some members of the Lilliaceae, 

Iridaceae, and Amaryllidaceae. J. Exp. Bot. 26:253–62. 

156. Hussey, G. 1980. Propagation of some 

members of the Liliaceae, Iridaceae and Amaryllidaceae 

by tissue culture: Petaloid monocotyledons. In C. D. 

Brickell, D. F. Cutler, and M. Gregory, eds. Linnean 

Soc. Symp. Ser. 8. London: Academic. 

157. Ilan, A., M. Ziv, and A. H. Halevy. 1995. 

Propagation of corm development of Brodiaea in liquid 

cultures. Scientia Hort. 63:101–12. 

158. Imanishi, H. 1993. Freesia. In A. De 



159. Jackson, H. C. 1975. Propagation and culture 

of African violets. Comb. Proc. Intl. Plant Prop. Soc. 

25:269–71. 

160. Jamieson, A. C. 1988. New Zealand callas. 

Grower Talks 51:56–60. 

161. Jeham, H., D. Courtois, C. Ehret, K. 

Lerch, and V. Petiard. 1994. Plant regeneration in Iris 

pallida Lam. and Iris germanica L. via somatic embryogenesis 

from leaves, apices and young flowers. Plant 

Cell Rpts. 13:671–75. 

162. Jenks, M., M. Kane, F. Morousky, D. 

McConnell, and T. Sheehan. 1990. In vitro establishment 

and epiphyllous plantlet regeneration of Nymphaea 

‘Daubeniana.’ HortScience 25:1664. 

163. Johnson, B. B. 1978. In vitro propagation 

of gloxinia from leaf explants. HortScience 13:149–50. 

164. Jones, R. O., R. L. Geneve, and S. T. 

Kester. 1994. Micropropagation of gas plant 

(Dictamnus albus L.). J. Environ. Hort. 12:216–18. 

165. Jungnickel, F., and S. Zaid. 1992. 

Micropropagation of African violets (Saintpaulia spp. 

and cvs.). In Y. P. S. Bajaj, ed. Biotechnology in agriculture 



166. Kallak, H., M. Reidla, I. Hilpus, and K. 

Virumae. 1997. Effects of genotype, explant source and 

growth regulators on organogenesis in carnation callus. 

Plant Cell Tiss. Organ Cult. 51:127–35. 

167. Kane, M. E., T. J. Sheehan, and F. H. 

Ferwerda. 1988. In vitro growth of American lotus 

embryos. HortScience 23:611–13. 

168. Kaukovirta, E. 1973. Effects of temperature 

and light intensity on the growth of Senecio hybridus 

Hyl. seedlings. Acta Hort. 31:63–9. 

169. Kelly, J. W., and J. J. Frett. 1986. 

Photoperiodic control of growth in water lilies. 

HortScience 21:151. 

170. Khan, M. R. I., J. K. Heyes, and D. Cohen. 

1988. Plant regeneration from oca (Oxalis tuberosa 

M.): The effect of explant type and culture media. 


171. Khehra, K., C. Lowe, M. R. Davey, and J. 

B. Power. 1995. An improved micropropagation system 

for chrysanthemum based on Pluronic 

F-68-supplemented media. Plant Cell Tiss. Organ Cult. 

41:87–90.


172. Kim, Y. S., E. H. Park, S. O. Yoo, J. S. Eun, 

and W. S. Song. 1991. In vitro propagation of ranunculus 

(Ranunculus asiaticus L.). I: Embryogenic callus 

induction and somatic embryogenesis. J. Korean Soc. 

Hort. Sci. 32:401–10. 

173. King, J. J., and M. P. Bridgen. 1990. 

Environmental and genotypic regulation of Alstroemeric 

seed germination. HortScience 25:1607–9. 

174. King, P. 1997. Production of Epimediums by 

division. Comb. Proc. Intl. Plant Prop. Soc. 47:521–22. 

175. Kitto, S. L., and A. Hoopes. 1992. Micropropagation 

and field establishment of Tiarella cordifolia. 

J. Environ. Hort. 10:171–74. 

176. Klesser, P. J., and D. D. Kel. 1976. Virus 

diseases and tissue culture of some South African flower 

bulbs. Acta Hort. 59:71–6. 

177. Knauss, J. F. 1976. A partial tissue culture 

method for pathogen-free propagation of selected fern 

from spores. Proc. Fla. State Hort. Soc. 89:363–65. 

178. Koh, Y. C., and F. T. Davies, Jr. 1997. 

Micropropagation of Cryptanthus with leaf explants with 

attached intercalary meristems, excised from greenhouse 

stock plants. Scientia Hort. 70:301–7. 

179. Kononowicz, H., and J. Janick. 1984. In 

vitro propagation of Vanilla planifolia. HortScience 

19:58–9. 

180. Kothari, S. L., and N. Chandra. 1984. In 

vitro propagation of African marigold. HortScience 

19:703–5. 

181. Kramer, J. 1971. How to grow African violets. 

4th ed. Menlo Park, CA: Lane. 

182. Kromer, K. D., and K. Kukulczanka. 1985. 

In vitro cultures of meristem tips of Canna indica (L.). 

Acta Hort. 251:147–53. 

183. Kukulczanka, K., K. Kromer, and B. 

Cvzanstka. 1989. Micropropagation of Fritillaria 

melengris L. through tissue culture. Acta Hort. 

251:147–53. 

184. Kunisaki, J. T. 1975. In vitro propagation of 

Cordyline terminalis (L.) Kurth. HortScience 10:601–2. 

185. Kunisaki, J. T. 1980. In vitro propagation of 

Anthurium andreanum Lind. HortScience 15:508–9. 

186. Kusey, W. E., Jr., P. A. Hammer, and T. C. 

Weiler. 1980. In vitro propagation of Gypsophila paniculata 

L. ‘Bristol Fairy.’ HortScience 15:600–1. 

187. Lalibert, S., L. Chretien, and J. Vieth. 

1985. In vitro plantlet production from young capitulum 

explants of Gerbera jamesonii. HortScience 

20:137–39. 

188. Lane, B. C. 1981. A procedure for propagating 

ferns from spore using a nutrient agar solution. 

Comb. Proc. Intl. Plant Prop. 30:94–7. 


189. Lawson, G. M., and P. B. Goodwin. 1985. 

Commercial production of kangaroo paws. Comb. 


190. Lazarte, J. E., M. S. Gaiser, and O. R. 

Brown. 1982. In vitro propagation of Epiphyllum 

chrysocardium. HortScience 17:84. 

191. Lazcano, C. A., F. T. Davies, Jr., A. A. 

Estrada-Luna, S. A. Duray, and V. Olalde-Portugal. 

1999. Effect of auxin and wounding on adventitious 

root formation of prickly-pear cactus cladodes. 

HortTechnology 9:99–102. 

192. Le Nard, M., and A. A. De Hertogh. 1993. 

Tulipa. In A. De Hertogh and M. Le Nard, eds. The 


pp. 617–82. 

193. Lee, C. I., and H. C. Kohl. 1985. Note on 

vegetative reproduction of Cyclamen indicum. The 

Plant Propagator 31:4. 

194. Lee, C. W., R. M. Skirvin, A. I. Soltero, and 

J. Janick. 1977. Tissue culture of Salpiglossis sinuata L. 

from leaf discs. HortScience 12:547–49. 

195. Leiss, J. 1998. Propagation of Phlox paniculata 

from root cuttings. Comb. Proc. Intl. Plant Prop. 

Soc. 48:326–27. 

196. Lilien-kipnis, H., and M. Kochba. 1987. 

Mass propagation of new Gladiolus hybrids. Acta Hort. 

212:631–38. 

197. Lindgren, D. T., and B. McCown. 1992. 

Multiplication of four penstemon species in vitro. 


198. Liu, L., and D. W. Burger. 1986. In vitro 

propagation of Easter lily from pedicels. HortScience 

21:1437–38. 

199. Lyons, R. E., and R. E. Widmer. 1980. 

Origin and historical aspects of Cyclamen persicum 

Mill. HortScience 15:132–35. 

200. Matsuo, E., and J. M. van Tuyl. 1986. Early 

scale propagation results in forcible bulbs of Easter lily. 


201. McComb, J. A., and S. Newton. 1981. 

Propagation of kangaroo paws using tissue culture. 


202. McKay, M. E., D. E. Bythe, and J. A. 

Tommerup. 1981. The effects of corm size and division 

of the mother corm in gladioli. Aust. J. Expt. Agric. 

Animal Husbandry 21:343–48. 

203. McMillan, R. N. 1980. Cyclamen production 

problems. Comb. Proc. Inter. Plant Prop. Soc. 

29:173–76. 

204. McRae, E. A. 1978. Commercial propagation 

of lilies. Comb. Proc. Intl. Plant Prop. Soc. 

28:166–69.



205. Mekers, O. 1977. In vitro propagation 

of some Tillandsioideae (Bromeliaceae). Acta Hort. 

78:311–20. 

206. Meyer, H. J., and J. Van Stadden. 1991. 

Rapid in vitro propagation of Aloe barbandensis Mill. 


207. Meyer, M. M., Jr. 1976. Propagation of 

daylilies by tissue culture. HortScience 11:485–87. 

208. Meyer, M. M., Jr. 1980. In vitro propagation 

of Hosta sieboldianum. HortScience 15:737–38. 

209. Meynet, J. 1993. Anemone. In A. De 

Hertogh and N. Le Nard, eds. The Physiology of flowering 


210. Meynet, J. 1993. Ranunculus. In A. De 



211. Meynet, J., and A. Cuclos. 1990. Culture 

in vitro de la renoncule des fleuristes (Ranunculus asiaticus 

L.). Agronomie 10:157–62. 

212. Mikkelsen, B. P., and K. C. Sink, Jr. 1978. 

In vitro propagation of Rieger Elatior begonias. 


213. Miller, C. T. 2005. Photoperiod and stock 

plant age effects on shoot, stolon, and rhizome formation 

response from leaf cuttings of Achimenes. Acta 

Hort. 673:349–54. 

214. Minocha, S. C. 1985. In vitro propagation 

of Dionaea muscipula. HortScience 20:216–17. 

215. Moe, R. 1993, Liatris. In A. De Hertogh 

and M. Le Nard, eds. The physiology of flowering bulbs. 

Amsterdam: Elsevier. pp. 381–90. 

216. Monette, P. L. 1992. Micropropagation of 

Inca Lily (Alstroemeria spp.). In Y. P. S. Bajaj, ed. 



pp. 1–18. 

217. Morel, G. M. 1966. Meristem culture: 

Clonal propagation of orchids. Orchid Digest 30:45–9. 

218. Murashige, T., M. Serpa, and J. B. Jones. 

1974. Clonal multiplication of Gerbera through tissue 

culture. HortScience 9:175–80. 

219. Nakano, M., Y. Hoshino, and M. Mii. 

1994. Adventitious shoot regeneration from cultured 

petal explants of carnation. Plant Cell Tiss. Organ Cult. 

36:15–20. 

220. Nakano, M., D. Niimi, D. Kobayashi, and 

A. Watanabe. 1999. Adventitious shoot regeneration 

and micropropagation of hybrid tuberous begonia 

(Begonia x tuberhybrida Voss). Scientia Hort. 

79:245–51. 

221. Natali, L., I. C. Sanchez, and A. Cavallini. 

1990. In vitro culture of Aloe barbadensis Mill.: 

Micropropagation from vegetative meristems. Plant 


222. Nathan, M. J., C. J. Goh, and P. P. Kumar. 

1992. In vitro propagation of Heliconia psittacorum by 

bud culture. HortScience 27:450–52. 

223. Nau, J. 1993. Ball culture guide: The encyclopedia 

of seed germination. Batavia, IL: Ball Pub. 

224. Newbury, H. J., E. A. B. Aitken, N. J. 

Atkinson, and B. V. Ford-Lloyd. 1992. 

Micropropagation of snapdragon (Antirrhinum majus 

L.). In Y. P. S. Bajaj, ed. Biotechnology in agriculture and 

forestry. Vol. 20. High-tech and micropropagation IV. 

Berlin: Springer-Verlag. pp. 19–33. 

225. Nomizu, T., Y. Niimi, S. Kasahara. 2003. 

In vitro micropropagation of ‘Yukiwariso’ (Hepatica 

nobilis Schreber var. japonica f. magna) by leaf segment 

culture. J. Jap. Soc. Hort. Sci.72:205–11. 

226. Nowak, J., and R. M. Rudnicki. 1993. 

Hyacinthus. In A. De Hertogh and M. Le Nard, eds. 

The physiology of flowering bulbs. Amsterdam: Elsevier. 

pp. 235–48. 

227. Ohki, S., and S. Sawaki. 1999. The effects 

of inorganic salts and growth regulators on in vitro 

shoot proliferation and leaf chlorophyll content of 

Delphinium cardinale. Scientia Hort. 81:149–58. 

228. Okubo, H. 1993. Hippeastrum (Amaryllis). 

In A. De Hertogh, and M. Le Nard, eds. The physiology 

of flowering bulbs. Amsterdam: Elsevier. pp. 

321–34. 

229. Peck, D. E. 1984. In vitro propagation of 

Begonia x tuberhydra from leaf sections. HortScience 

19:395–97. 

230. Peck, D. E. 1984. In vitro vegetative propagation 

of cape primrose using the corolla of the flower. 


231. Peck, D. E., and B. G. Cumming. 1986. 

Beneficial effects of activated charcoal on bulblet production 

in cultures of Muscari armeniacum. Plant Cell 

Tiss. Organ Cult. 6:9–14. 

232. Pence, V. C., and V. G. Soukup. 1993. 

Factors affecting the initiation of mini-rhizomes from 

T. erectum and T. grandiflorum tissues in vitro. Plant 


233. Perl, P. 1977. Ferns. Alexandria, VA: Time- 

Life Books. 

234. Perl, P. 1978. Cacti and succulents. 

Alexandria, VA: Time-Life Books. 

235. Pfister, J. M., and J. M. Widholm. 1984. 

Plant regeneration from snapdragon tissue culture. 


236. Pierik, R. L. M., and H. H. M. Steegmans. 

1976. Vegetative propagation of Freesia through


isolation of shoots in vitro. Netherlands J. Agric. Science 

24:274–77. 

237. Piqueras, A., J. M. van Huylenbroeck, B. 

H. Han, and P. C. Debergh. 1998. Carbohydrate partitioning 

and metabolism during acclimatization of 

micropropagated Calathea. Plant Growth Regul. 

26:25–31. 

238. Platt, G. C. 1985. Propagation of the 

cordylines by vegetative means. Comb. Proc. Intl. Plant 

Prop. Soc. 35:364–66. 

239. Poole, R. T., and C. A. Conover. 1987. 

Vegetative propagation of foliage plants. Comb. Proc. 


240. Prakash, J. 2009. Micropropagation of 

ornamental perennials: progress and problems. Acta 

Hort. 812:289–94. 

241. Preece, J. E., and K. P. Ripley. 1992. In 

vitro culture and micropropagation of Euphorbia sp. In 

Y. P. S. Bajaj, ed. Biotechnology in agriculture and 



242. Quay, L., J. A. McComb, and K. W. Dixon. 

1995. Methods for ex vitro germination of Australian 

terrestrial orchids. HortScience 30:182. 

243. Ramachandra, S., and H. Khatamian. 

1989. Micropropagation of Peperomia and Begonia 

using petiole segments. HortScience 24:153. 

244. Ramcurez-Malagcon, R. 2008. In vitro 

propagation of three Agave species used for liquor distillation 

and three for landscape. Plant Cell Tiss. Organ 

Cult. 94:201–7. 

245. Rauch, F. D., and R. M. Yamakawa. 1980. 

Effects of auxin on rooting of Ixora acuminata. 


246. Raviv, M., E. Putieusky, and D. 

Sanderovich. 1984. Rooting stem cuttings of sage 

(Salvia officinalis L.). The Plant Propagator 30:8–9. 

247. Raward, I. D. 1975. Propagation of 

Codiaeum (croton) by tip cuttings. Comb. Proc. Intl. 

Plant Prop. Soc. 25:386. 

248. Redwood, G. N., and J. C. Bowling. 1990. 

Micropropagation of Nepenthes species. Bot. Gardens 

Microprop. News 1:19–20. 

249. Richwine, A. M., J. L. Tipton, and G. 

Thompson. 1995. Establishment of Aloe, Gasteria, and 

Haworthia shoot cultures from inflorescence explants. 


250. Robacker, C. D., and W. L. Corley. 1992. 

Plant regeneration of pampas grass from immature 

inflorescences cultured in vitro. HortScience 27:841–43. 

251. Roberts, D. J. 1965. Modern propagation 

of ferns. Comb. Proc. Intl. Plant Prop. Soc. 15:317–21. 


252. Rockwell, F. F., G. C. Grayson, and J. de 

Graff. 1961. The complete book of lilies. Garden City, 

NY: Doubleday. 

253. Roest, S., and G. S. Bokelmann. 1975. 

Vegetative propagation of Chrysanthemum morifolium 

Ram in vitro. Scientia Hort. 3:317–30. 

254. Rogers, R. W. 1995. Divide and conquer: 

Propagation of herbaceous and tree peonies. Comb. 


255. Rudnicki, R. M., and J. Nowak. 1993. 

Muscari. In A. De Hertogh and M. Le Nard, eds. The 


pp. 455–62. 

256. Samfield, D. M., J. M. Zajicek, and B. G. 

Cobb. 1988. The effects of osmoconditioning on 

herbaceous perennial seed germination at different 

temperatures. HortScience 23:750. 

257. Schnabelrauch, L. S., and K. C. Sink. 1979. 

In vitro propagation of Phlox subulata and Phlox paniculata 

tissue culture. HortScience 14:607–8. 

258. Schwartz, M. A., R. N. Payne, and G. Sites. 

1985. Residual effects of chlormequat on garden performance 

in sun and shade of seed and cutting propagated 

cultivars of geraniums. HortScience 20:368–70. 

259. Schwenkel, H. G., and J. Grumwaldt. 

1988. In vitro propagation of Cyclamen persicum Mill. 

Acta Hort. 226:659–62. 

260. Scott, M., and M. E. Marson. 1967. Effects 

of mist and basal temperature on the regeneration of 

Saintpaulia ionantha Wendl. from leaf cuttings. 

Horticultural Res. 7:50–60. 

261. Sheehan, T. J. 1983. Recent advances in 

botany, propagation and physiology of orchids.Hort. 

Rev. 5:279–315. 

262. Sheerin, P. 1974. Propagation of various 

types of begonia. Comb. Proc. Intl. Plant Prop. Soc. 

24:292–93. 

263. Shoemaker, C. A., and W. H. Carlson. 1992. 

Temperature and light affect seed germination of 

Begonia semperflorens-cultorum. HortScience 27:181. 

264. Simmonds, J. 1992. Micropropagation of 

Begonia spp. In Y. P. S. Bajaj, ed. Biotechnology in agriculture 



265. Simmonds, J., and T. Werry. 1987. 

Liquidshake culture for improved micropropagation of 

Begonia x hiemalis. HortScience 22:122–24. 

266. Singletary, S. R., and S. A. Martin. 1998. 

IBA-K induced rooting in perennials. Comb. Proc. Intl. 


267. Slabbert, M. M., M. H. De Bruyn, D. I. 

Ferreira, and J. Pretorius. 1995. Adventitious in vitro



plantlet formation from immature floral stems of 

Crinum macowanii. Plant Cell Tiss. Organ Cult. 

43:51–7. 

268. Slocum, P. D. 1985. Propagating water lilies 

and aquatics. Brooklyn Botanic Garden Record 41:25–8. 

269. Small, D. J. 1986. Propagation of choice 

alpines. Comb. Proc. Intl. Plant Prop. Soc. 36:241–44. 

270. Smith, R. H., and A. E. Nightingale. 1979. 

In vitro propagation of Kalanchoe. HortScience 14:20. 

271. Smith, R. H., and R. E. Norris 1983. In 

vitro propagation of African violet chimeras. 


272. Solem, M. 1988. Torenia. Grower Talks 

52:18. 

273. Solt, S. 1998. Commercial propagation of 

Trillium. Comb. Proc. Intl. Plant Prop. Soc. 48:329–32. 

274. Sriskandarajahi, S., and R. M. Skirvin. 

1991. Effect of NH 4NO 3 level on philodendron root 

development in vitro. HortTechnology 1:37–8. 

275. St. Hilaire, R., C. A. Fierro-Berwart, and 

C. A. Perez-Mumoz. 1996. Adventitious root formation 

and development in cuttings of Mussaenda erythrophylla 

L. Schum. & Thonn. HortScience 31:1023–25. 

276. Standifer, L. C., E. N. O’Rourke, and R. 

Porche-Sorbet. 1984. Propagation of Haworthia from 

floral scapes. The Plant Propagator 30:4–6. 

277. Stanilova, M. I., V. P. Ilcheva, and N. A. 

Zagorska. 1994. Morphogenetic potential and in vitro 

micropropagation of endangered plant species 

Leucojum aestivum L. and Lilum rhodopaeum Delip. 

Plant Cell Rpts. 13:451–53. 

278. Stapfer, R. E., and C. W. Heuser. 1985. In 

vitro propagation of periwinkle. HortScience 

20:141–42. 

279. Stapfer, R. E., and C. W. Heuser. 1986. 

Rapid multiplication of Heuchera sanguinea Engelm. 

‘Rosamundi’ propagated in vitro. HortScience 

21:1043–44. 

280. Stapfer, R. E., C. W. Heuser, and C. F. 

Deneke. 1985. Rapid multiplication of Veronica ‘Red 

Fox’ propagated in vitro. HortScience 20:866–67. 

281. Start, N. D., and B. G. Cumming. 1976. 

In vitro propagation of Saintpaulia ionantha Wendl. 


282. Stefanis, J. P., and R. W. Langhans. 1980. 

Factors affecting the production and propagation of 

xerophytic succulent species. HortScience 15:504–5. 

283. Stephens, L. C., S. L. Krell, and J. L. 

Weigle. 1985. In vitro propagation of Java, New 

Guinea and Java New Guinea Impatiens. HortScience 

20:362–63. 

284. Stephens, L. C., J. L. Weigle, S. L. Krell, 

and K. Han. 1991. Micropropagation of Impatiens. In 

Y. P. S. Bajaj, ed. Biotechnology in agriculture and 



285. Stewart, J., and E. Hennessy. 1981. Orchids 

of Africa. Boston: Houghton Mifflin. 

286. Still, S. M. 1994. Manual of herbaceous 

ornamental plants. 4th ed. Champaign, IL: Stipes Publ. 

287. Stimart, D. P. 1986. Commercial micropropagation 

of florist flower crops. In R. H. 

Zimmerman et al., eds. Tissue culture as a plant production 

system for horticultural crops. Dordrecht: Martinus 

Nijhoff Publishers. 

288. Stimart, D. P., and P. D. Ascher. 1978. 

Tissue culture of bulb scale sections for asexual propagation 

of Lillium longiflorum Thumb. J. Amer. Soc. 

Hort. Sci. 103:182–84. 

289. Stimart, D. P., and J. F. Harbage. 1989. 

Shoot proliferation and rooting in vitro propagation of 

Liatris spicata. HortScience 24:835–36. 

290. Stimart, D. P., J. C. Mather, and K. R. 

Schroeder. 1998. Shoot proliferation and rooting in 

vitro of Pulmonaria. HortScience 33:339–41. 

291. Stokes, P. 1984. Hardy ferns. Comb. Proc. 


292. Sul, I. W., and S. S. Korban. 1998. 

Influence of bombardment with BA-coated microprojectiles 

on shoot organogenesis from Phlox paniculata 

L. and Pinus pinea L. tissues. In Vitro Cell Dev. Biol.— 

Plant 34:300–2. 

293. Sutter, E. G. 1986. Micropropagation of 

Ixia viridifolia and a Gladiolus x homoglossum hybrid. 


294. Takayama, S. 1990. Begonia. In P.V. 

Ammirato, D.A. Evans, W.R. Sharp, and Y.P.S. Bajaj, 

eds. Handbook of plant cell culture. McGraw-Hill. 

pp. 253–83. 

295. Tanabe, M. J. 1980. Effect of depulping 

and growth regulators on seed germination of Alyxia 

olivaeformis. HortScience 15:199–200. 

296. Tanabe, M. J. 1982. Single node stem propagation 

of Alyxia olivaeformis. HortScience 17:50. 

297. Thompson, P. A., and S. A. Cox. 1979. Germination 

responses of half-hardy annuals. 2. China 

aster (Callistephus chinensis). Seed Science and Technol. 

7:201–7. 

298. Thorn-Horst, A., R. K. Horst, S. H. Smith, 

and W. A. Oglevee. 1977. A virus-indexing tissue culture 

system for geraniums. Flor. Rev. 160(4148):28–9, 

72–4.


299. Torres, K. C., and N. J. Natarella. 1984. In 

vitro propagation of Exacum. HortScience 19:224–25. 

300. Tsuro, M., M. Koda, and M. Inowe. 1999. 

Comparative effect of different types of cytokinin for 

shoot formation and plant regeneration from leafderived 

callus of lavender (Lavandula vera DC). 


301. Ulrich, M. R., F. T. Davies, Jr., Y. C. Koh, 

S. A. Duray, and J. N. Egilla. 1999. Micropropagation 

of Crinum ‘Ellen Bosanquet’ by tri-scales. Scientia 

Hort. 82:95–102. 

302. Upadhyaya, A., T. D. Davis, D. Sankhla, 

and N. Sankhla. 1992. Micropropagation of Lupinus 

texensis from cotyledonary node explants. HortScience 

27:1222–23. 

303. Van Brenk, G., and M. Benschop. 1993. 

Nerine. In A. De Hertogh and M. Le Nard, eds. The 


pp. 559–88. 

304. Van de Pol, P. A., and T. F. Van Hell. 1988. 

Vegetative propagation of Streilitzia reginae. Acta Hort. 

226:581–86. 

305. Van der Linde, P. C. G., and J. A. Schipper. 

Micropropagation of iris with special reference to Iris x 

hollandica Tub. In Y. P. S. Bajaj, ed. Biotechnology in 

agriculture and forestry. Vol. 20. High-tech and micropropagation 


306. Van Dyk, M., and R. Currah. 1983. 

Vegetative propagation of prairie forbs native to southern 

Alberta, Canada. The Plant Propagator 28:12–4. 

307. Van Rensburg, J. G. J., B. M. Vcelar, and P. 

A. Landby. 1989. Micropropagation of Ornithogalum 

maculatum. South African J. Bot. 55:137–39. 

308. Varadarajan, G. S., U. Varadarajan, and R. 

D. Locy. 1993. Application of tissue culture techniques 

maintain a rare species, Puya tuberosa. 

J. Bromeliad Soc. 43:12–8. 

309. Verron, P., M. Le Nard, and J. Cohat. 

1995. In vitro organogenic competence of different 

organs and tissues of lily of the valley ‘Grandiflora of 

Nantes’. Plant Cell Tiss. Organ Cult. 40:237–42. 

310. Vinterhalter, D. V. 1989. In vitro propagation 

of green-foliaged Dracaena fragrans Ker. Plant Cell 

Tiss. Organ Cult. 17:13–9. 

311. Von Hentig, W. U., M. Fisher, and K. 

Köhler. 1984. Influence of daylength on the production 

and quality of cuttings from Fuchsia mother plants. 


312. Wang, Y. T. 1987. Effect of warm-medium, 

light intensity, BA and parent leaf on propagation of 

golden pothos. HortScience 22:597–99. 


313. Wang, Y. T. 1987. Effect of temperature, 

duration and light during simulated shipping on quality 

and rooting of croton cuttings. HortScience 22:1301–2. 

314. Wang, Y. T. 1987. Influence of light and 

heated medium on rooting and shoot growth of two 

foliage plant species. HortScience 23:346–47. 

315. Wang, Y. T., and C. A. Boogher. 1988. 

Effect of nodal position, cutting length, and root retention 

on the propagation of golden pothos. HortScience 

23:347–49. 

316. Wartidininghsih, N., and R. L. Geneve. 

1994. Source and seed quality influence germination in 

purple coneflower (Echinacea purpurea). HortScience 

29:1443–44. 

317. Wartidininghsih, N., and R. L. Geneve. 

1994. Osmotic priming or chilling stratification 

improve seed germination of purple coneflower 

(Echinacea purpurea). HortScience 29:1445–48. 

318. Watad, A. A., M. Kochba, A. Nissim, and 

V. Gaba. 1995. Improvement of Aconitum nepellus 

micropropagation by liquid culture on floating membrane 

rafts. Plant Cell Rpt. 14:345–48. 

319. Watelet-Gonad, M. C., and J. M. Favre. 

1981. Miniaturization et rajeunissement chez Dahlia 

variabilis (variete Television) cultive in vitro. Ann. 

Sciences Naturelles Bot., Paris. pp. 51–67. 

320. Welander, T. 1978. In vitro organogenesis 

in explants from different cultivars of Begonia x 

hiemalis. Physiol. Plant. 41:142–45. 

321. Widmer, R. E. 1980. Cyclamens. In R.A. 

Larson, ed. Introduction to floriculture. New York: 

Academic Press. 

322. Wikesjö, J. 1982. Growing hybrid Achimenes 

as a pot plant. Florists’ Review 168:34, 120–22. 

323. Wilfret, G. J. 1993. Caladium. In A. De 



324. Wilson, H. V. 1980. Saintpaulia species. 

Amer. Hort. 58:35–9. 

325. Yanagawa, T., and I. Ito. 1988. Differences 

in the capacity for bulblet regeneration between bulbscale 

explants excised from different parts of 

Hymenocallis and Ornithogalum bulbs. J. Japan. Soc. 

Hort. Sci. 57:454–61. 

326. Yanagawa, T., and Y. Sakanishi. 1980. 

Studies on the regeneration of excised bulb tissues of 

various tunicated-bulbous ornamentals. 1. Regenerative 

capacity of the segments from different parts of bulb 

scales. J. Japan. Soc. Hort. Sci. 48:495–502. 

327. Yantcheva, A., M. Vlahova, and A. 

Antanassov. 1998. Direct somatic embryogenesis and



plant regeneration of carnation (Dianthus caryophyllus 

L.). Plant Cell Rpt. 18:148–53. 

328. Zieslin, N., and A. Keren. 1980. Effects of 

rootstock on cactus grafted with an adhesive. 


329. Zimmer, K. 1985. Eremurus. In A. H. 

Halevy, ed. Handbook of flowering, Vol. II. Boca Raton, 

FL: CRC Press. pp. 466–69. 

330. Zimmerman, T. W., F. T. Davies, Jr., and J. 

M. Jajicek. 1991. In vitro and macropropagation of the 

wildflower Dyssodia pentacheta (D.C.) Robins. 


331. Ziv, M., N. Hertz, and Y. Biran. 1983. 

Vegetative reproduction of Allium ampeloprasum L. in 

vivo and in vitro. Israel J. Bot. 32:1–9. 

332. Ziv, M., and J. Lilien-Kipnis. 1990. 

Gladiolus. In P. V. Armmirato, D. A. Evans, 

W. R. Sharp, and Y. P. S. Bajaj, eds. Handbook of 

plant cell culture. New York: McGraw-Hill. 

pp. 461–78.

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