July is the month of Monardas here. We have one straight species (Wild Bergamot, Monarda fistulosa) and three hybrid cultivars: ‘Raspberry Wine’, ‘Purple Rooster’, and what I suspect is a home-grown hybrid that looks like a cross between Wild Bergamot and ‘Purple Rooster’.
Gardeners interested in Monarda should check out two trials of various species and cultivars conducted by the Mt. Cuba Center (published earlier this year) and the Chicago Botanic Garden (published back in 1998).
One thing I found a bit dismaying was how poorly Wild Bergamot did in both studies. The Mt. Cuba Center gave it an overall rating of fair to poor, while the CBG deemed it “very poor” in terms of mildew resistance. This made me feel like a fan who watches a favorite athlete fumble a play during a big game, as I have a large clump of Wild Bergamot that I’m very fond of.
Moreover, in our garden this plant has usually had only modest troubles with downy mildew. The lavender flowers of Wild Bergamot are smallish but prolific. It spreads by rhizome but not nearly as aggressively as ‘Raspberry Wine’ and some other Monardas. My main complaint against Wild Bergamot is that it tends to grow too tall, 4-5′, and requires some support.
In terms of other straight species, M. diyma – usually known as Bee Balm, fared even worse in the trials than the Wild Bergamot. On the other hand, Eastern Bee Balm (M. bradburiana) was rated as “Excellent” by CBG, though it wasn’t included in the Mt. Cuba trial.
. If I had known about Eastern Bee Balm when I started my garden I would have planted some, as it is obligingly compact – just about 2′ tall.
‘Raspberry Wine’ was highly rated in both trials. I concur with that assessment. Lots of big red-purple flowers and foliage that is almost always disease-free. Tends to grow taller than is ideal, but responds well to cutting back, and spreads very aggressively by rhizome.
‘Purple Rooster’ was rated “excellent” in the Mt. Cuba trials. It stands out for its purple flowers, compact stature (about 3′) and mildew resistance. It wasn’t included in the CBG trials.
Cultivars rated highly by both CBG and Mt. Cuba were ‘Colrain Red’, ‘Gardenview Scarlet’, and ‘Violet Queen’. Some plants, like the M. fistulosa cultivar ‘Claire Grace’, had conflicting evaluations – in this case, rated highly by Mt. Cuba and poorly by CBG. This may be due to differing conditions between Mt. Cuba’s Mid-Atlantic climate and the midwestern climate of CBG. Unfortunately, the lists of plants tested in the two trials overlapped but were not identical.
The Mt. Cuba trial attempted to test each plant’s attractiveness to hummingbirds and to butterflies and moths. For hummingbirds, the biggest attractor by far was M. didyma ‘Jacob Cline’. ‘Raspberry Wine’ was one of the top five. The top butterfly and moth attractor was M. fistulosa ‘Claire Grace’.
It’s interesting that nine out of ten plants most attractive to hummingbirds and to butterflies/moths in this trial were cultivars. Only straight species Bee Balm (M. didyma) made it into the top ten (it ranked fourth in hummingbird visits). The authors note that there are “horticulturally desirable characteristics of cultivars (ie improved flower production and longer bloom times) that can have a positive impact on ecological function.” Of course, many (most?) cultivars are less beneficial for pollinators than the straight species, especially those with double blooms.
The trial did not include bees and wasps, but the Mt. Cuba folks have another study coming that looks at how different flower characteristics affect pollinator visitation. My own experience is that both Wild Bergamot and ‘Raspberry Wine’ are constantly being visited by numerous bees, especially bumblebees.
Anyhow, if you are thinking about planting Monardas in your garden, I would recommend that you check out the CBG and Mt. Cuba reports.
gardeninacity 
Thank you–I will check out these trials. I’ve been following @cassianschmidt on Instagram for some amazing Monarda didyma trials that I believe are going on at Weinheim. You’re right – July is the month for Monarda. And living near the CBG, I’ll stop in soon. Many years ago I had a yard full of Jacob Cline and the color and freshness of the plant has stayed with me. Now so many other beauties are enjoyed – who says the world isn’t getting better!
Last time we were at CBG some things were suffering from the drought. I’m hoping the rain has improved the gardens.
That photo of the swallowtail on the ‘Raspberry Wine’ is glorious! Apparently you and Monarda get along quite well — what a spread!
Yes, they are pretty happy here.
Thanks for sharing the study, Jason. I really enjoy the stands of Monarda I have here, as do the hummers and bees. The red one I planted with hummers in mind. I do have a problem with powdery mildew, however, and with all the rain we’ve the past two weeks, I expect it is going to be bad this year.
So far here it’s not too bad, but we’ll see.
This was interesting. We share M. fistulosa, but I’ve never heard it called wild bergamot, even though my books include that name. In fact, of the seven native Monarda species I know, all go by ‘beebalm’ or ‘horsemint’ — although ‘Monarda’ sometimes is used as a common name. I can’t remember ever seeing a cultivar; the plants look quite different from the natives I’m accustomed to.
I was surprised to see Amsonia and Monarda blooming together at the Lurie Garden. Here, both species of Amsonia are long gone before the Monardas start to bloom. Perhaps the answer to that is Lurie’s use of cultivars. They surely are pretty together!
Actually the Amsonia was just foliage, I should have been clearer. The blue flowers in back were perennial Salvias.
See? This proves I can’t identify Salvias, or tell them from Amsonia. I saw blue, and made the mistake of not looking more closely!
Right now, bee balm is the star of the garden in my backyard. Bees love it, hummingbirds love it, and so do I. The splash of red makes me smile, and I really like the smell.
Same here, Laurie.
Those trials are overrated. Some people give them too much authority. They may be more accurate for regions of similar climate, but are not so practical where there are so many different climate zones and soil types within such small areas. I often grow plants that I like even though I do not expect them to perform well, simply because I have discriminating taste. Sometimes, I must find out for myself how well they will do . . . or not.
Maybe they are overrated, but I still find them interesting. There isn’t much else to go on when choosing new varieties.
Yes, sometimes that is all there is. They will not stop me from growing everything that I should not grow though.
I love the photo of the Lurie Garden, what a glorious combination of colours and plants.
Yes, I agree!
My experience of wild bee balm (M. fistulosa) blooming out at Horlock Prairie west of St. Charles, is its fragrance: A beautiful, dry, sweet herbal scent that perfumes the prairie.
Some people use the leaves to make a tea.
Raspberry Wine is such a standout gorgeous plant for me, I’ll definitely be looking for that one around here. Interesting point about cultivars and pollinators – I guess this is also why Geranium Rozanne tops the charts for pollinators, even though it’s a sterile hybrid, but for sheer number of blooms over a long period, it wins. But somehow I don’t like the idea of it being sterile.
‘Rozanne’ hasn’t performed that well for me, there are other Geraniums that I prefer.
She’s on my post today! Does pretty well on a shady rubbly slope where not much else grows. But I agree that there are more beautiful geraniums.
Opened a tab with the reports and will be checking them out this afternoon. My monarda (Panama Mix) is now blooming – it has definitely spread from last year, probably about twice as big as it was before, so I’ll be digging some up to transplant it elsewhere. I grew it from seed (Panama Mix) and I’ll have to see if it (or one that is similar) falls within those that were part of the study.
Looked up ‘Panama Mix’ – didn’t know there were multi-colored Monarda!
Beautiful. I have one kind, I’d have to look up what, and it’s always done terribly. For years it’s been the only plant in the bed to be gnawed and ragged by something I can’t see. It’s the sacrificial lamb now, and it may have a few pathetic flowers. It is a very aggressive spreader though!
The Monarda bradburiana combination is wonderful and your wild plants look lovely too.
Love your post about this trial and your findings in your own garden Jason. The bee balm in my gardens are all but spent, a few stragglers here and there. I also have Purple Rooster and have enjoyed it’s fairly vigorous quest for dominance. I move it around and share it with friends. I’ll definitely be looking for Raspberry Wine, what a beauty and a spreader that color is welcome here. I have ‘Pardon My Cerise’ and while beautiful, it’s been sorely docile. It hasn’t really gotten any larger than the original pot size it came in and I planted it years ago. It’s close in color to Raspberry Wine. Thanks to Sel, I’ll be searching out geranium Rozane now, too.
This is filled with great information. Your monardas make a great show. I like ‘Raspberry Wine’ and I think it must be what some of my neighbors grow. Mine’s the straight. M. didyma, which nearly disappeared for a couple years but is making a comeback. Not sure why. Beautiful beautiful butterfly. Have a good gardening week.
Your Monarda collection is impressive! Thank you for the Mt Cuba Center reference. Thus far, I’ve only found one Monarda that’s bloomed and returned for a second year in my SoCal garden, ‘Peter’s Purple’, which is hybrid of M. fistulosa ‘Claire Grace’ and M. bartlettii, a Mexican species. Heat and drought tolerance is an issue here, which unfortunately the study doesn’t pointedly address.
I like them all! We have a mildew problem here even on wild plants of various species, but not every year. This year is shaping up to be a good one for molds and mildews but I haven’t seen them yet. I hope they stay out of your garden.
I had some Wild Bergamot but it was overtaken by more chaotic plants that I hope to remove now that I don’t have to worry about them! I may very well be tempted to install some Raspberry Wine somewhere after seeing how it attracts hummingbirds. The Black Swallowtail on it is beautiful. Thanks for an informative and beautiful post.
The wild sort are lovely, but I do like the red ones more. It was funny to see your post this morning as I had just been checking on the name of mine for a future post! I am growing M. ‘Gardenview Scarlet’ and it is gorgeous… about 2 foot tall, no sign of mildew, sturdy plants and beautiful foliage as well as flowers. It’s the first time I have tried growing them for years and I am hoping they will spread a bit. We don’t have much variety on offer here but our nurseries are slowly getting better so I shall keep my eyes open for Raspberry Wine. Your photos are a great guide. 😃
I have some blooming right now but haven’t been able to enjoy them because it rains every single day. Your photos are wonderful especially the last one.
I have some kind of bergamot/bee balm growing in my garden, but I can’t seem to find any specific reference to it in my blog. It’s lavender but shortish, definitely not 4-5′ tall. I tried a cultivar named ‘Fireball’ once but the bees did not seem to like it (and it apparently did not like my yard). Your pix of ‘Raspberry Wine’ are winning me over to that cultivar.
Thanks for sharing all the trial info/links for bee balm. Yours are so beautiful! They put on quite the show. I grow raspberry wine, which has been a trooper in the shed bed, but this year it’s struggling. Who knows why? I also have the eastern bee balm, which I like because it’s short, spreads steadily but not aggressively, and blooms in May, well before the other. And pollinators like it. A winner all around!
I love Monarda. In summer we don’t worry about mildew here, as it is very dry. Spring and fall have been the worst times for mildew though, sometimes affecting our spearmint. The “Raspberry Wine” monarda is very beautiful.
Quite interesting. Over the years, I have tried three times (not recently) to grow monarda. It’s always failed for me- either from mildew or doesn’t return the second year. I see it growing elsewhere in other gardens in our area and it makes me wonder what I’m doing wrong! I briefly looked at the Mt. Cuba site and now (only 200 miles away!) I’m interested in visiting. It seems to have a wealth of information.
I inherited a stand of tall, nearly-true-red monarda along with the house and garden but have no idea which one it is. They are on the north side of the house, if you can believe it, being shouldered by huge abelia on one side and an aucuba on the other. I’m tempted to move some of them to a more ‘suitable’ spot but with my luck, they’d probably all die on me if I do, lol
Thanks for a very useful post, Jason as I’m planning to have a stand of monardas for the final border that I’m currently digging. I’ll have to look into the details of the trials. I wonder how the growing conditions are different. What I did find a surprise was the cultivars being better at attracting pollinators, grown for more flower production and longer flowering season, I guess that makes sense but it doesn’t always work that way around.