Gunnera

Scientific name

Gunnera L.

Common names

giant rhubarb

Family

Gunneraceae

Similar genera

Caltha, Darmera

Native distribution

almost exclusively in the southern hemisphere, tropical and temperatetemperate:
(adj) of the climatic zone between boreal and tropical
regions; New Zealand, Australia, Africa, Madagascar, South and Central America, and several Pacific Islands

Species cultivated

Gunnera cordifolia (Hook.f.) Hook.f.

G. manicata Linden ex Delchev.

G. magellanica Lam.

G. monoica Raoul

G. perpensa L.

G. prorepens Hook.f.

G. tinctoria (Molina) Mirb.

Adventive distribution

Gunnera manicata is introduced into Ireland and New Zealand.

G. tinctoria is introduced into New Zealand and California (United States).

Weed status

sometimes weedy

Habit

amphibious amphibious:
(adj) of a plant able to live on land or in water
to semi-aquatic, large and broad-leaved

Brief description

Perennial, rhizomatousrhizomatous:
(adj) possessing rhizomes
and stoloniferous. Stem highly compact and thick. Leaves basalbasal:
(adj) at or pertaining to the base, or point of attachment
; petiolepetiole:
(n) the stalk of a leaf
long, armed, sometimes with intrapetiolar cataphylls; leaf bladeblade:
(n) (syn. lamina) the flat, expanded part of a leaf, frond, or petal (excluding, e.g., the petiole)
ovate to reniform-cordate, simple to lobedlobed:
(adj) divided into (usually rounded) segments
, often rugoserugose:
(adj) wrinkled
, can be very large; apexapex:
(n) the point farthest from the point of attachment; the tip (often pointed)
round; base typically cordatecordate:
(adj) heart-shaped; in the form of two rounded lobes
; marginmargin:
(n) edge; rim
crenatecrenate:
(adj) (of a margin) with shallow, rounded teeth
to serrateserrate:
(adj) (of a leaf margin) bearing sharp teeth pointing forward or to the apex
; venationvenation:
(n) the arrangement of veins in a leaf
palmatepalmate:
(adj) (of leaves or venation) with lobes, leaflets, divisions or veins originating from the same point
. Inflorescenceinflorescence:
(n) the arrangement of flowers on the floral axis
of very small flowers in an axillaryaxillary:
(adj) in, of, or produced from an axil
or pseudoterminal paniclepanicle:
(n) an indeterminate, branched (often much-branched) inflorescence; the ultimate units may be of a different inflorescence type
, racemeraceme:
(n) an indeterminate, unbranched inflorescence having pedicelled flowers on a usually elongated axis (may be cymose)
, or spikespike:
(n) an indeterminate, unbranching inflorescence of sessile flowers or flower clusters on a usually elongated axis
; female flowers below, male above, bisexualbisexual:
(adj) having both male and female sexual reproductive structures on one individual or in one flower
in between. Fruit a small fleshy or leathery drupedrupe:
(n) fleshy indehiscent fruit in which the seed or seeds are surrounded by a hardened endocarp (as in a cherry)
with only 1 seed.

Natural habitat

wet meadows and gardens, on wet coastal cliffs, along streams, rivers, lakes, near and in swales, bogs, marshes, swamps and other wetland areas

Additional comments

Gunnera is the only angiosperm that has a symbiotic relationship with Nostoc, a cyanobacteria. Most of the approximately 70 species in the genus are amphibiousamphibious:
(adj) of a plant able to live on land or in water
to semi-aquatic. The large-sized Gunnera tinctoria is frequently cultivated.

  Gunnera perpensa ; photo: S.L. Winterton

Gunnera perpensa; photo: S.L. Winterton

  Gunnera perpensa  inflorescence; photo: S.L. Winterton

Gunnera perpensa inflorescence; photo: S.L. Winterton

  Gunnera tinctoria , emersed; photo: S.L. Winterton

Gunnera tinctoria, emersed; photo: S.L. Winterton

  Gunnera tinctoria  petiole; photo: S.L. Winterton

Gunnera tinctoria petiole; photo: S.L. Winterton

  Gunnera tinctoria  inflorescence; photo: S.L. Winterton

Gunnera tinctoria inflorescence; photo: S.L. Winterton

  Gunnera tinctoria  inflorescence; photo: S.L. Winterton

Gunnera tinctoria inflorescence; photo: S.L. Winterton