Several people have mentioned deformed Monarda blooms caused by a horsemint moth caterpillar. Search this forum for other. Threads on Monarda within the past week.

Martha

I saw that thread, but my blooms are not deformed per se; they are just aren't there. The top of the stem colors up a bit (to an ugly, dirty red) and then no blooms follow.

I did take a peek for a caterpillar, as I recall that thread mentioned something about some kind of caterpilllar, but I did not see any, and while I never looked specifically for them, I don't recall seeing any on my old pink and purple monarda either.

Dee

Well, I was able to get a few photos. Maybe this can help identify what's going on.

Here is an attempted close-up of one of the non-blooms. Sorry about the focus, but hopefully you can see that it is NOT a bloom!

Here's a wider shot of the clump

And here is what one of the few "blooms" looks like

diigerdee, the distorted flowers you're showing are the result of the horsemint catapilllar, same as I have.

You can actually see it in your last photo - look on the left, at the base of one of the petals sort of in the middle you see a thin white line - that's it. Looks like a thin white worm, until you look closely.

I meant to add - best advice I can give is cut off every flower and destroy them so that the catepillar hiding within is also killed.

And yes, those "non blooms" are the flowers. They've been attacked. If you look carefully, you'll see the culprit.

a2zmom, thanks for your reply. I don't see the white line you are referring to, and I took another look today outside to look for caterpillars (although I honestly don't know what I should be looking for - guess I should google it!) but didn't notice any.

I'll do a bit of research and look again. This is getting discouraging. In the last few years I've already ripped out two clumps of monarda, neither of which ever did well from the get-go. One was pink, one was purple, and both were seed-grown, so I thought perhaps they were just weak plants. This will be my third failure with this plant.

Well, I do appreciate you responding and I'll take another look.

Thank you!
Dee

I wouldn't rip out the whole plant just yet. If you cut off all the blooms, you should get another flush later in the season and that should be fine.

Back in 2007, I had the same problem and had to cut the entire plant down. Here it is last year:

{{gwi:248331}}

Perfectly fine as you can see.

Well, a2zmom, I went out to the garden several times over the last two days, and checked over and over, and didn't see anything until about the fourth time! NOW, I think I see what you mean. After checking every single stem, and seeing nothing, I found TWO little worms in one of the "non-blooms". Aha!

I just can't get over how the entire plant was basically devastated, but I can only find two little worms on ONE bloom! Either they do tremendous damage, or the rest of them can hide really well.

By the way, just to clarify, when I ripped out the other clumps of monarda, it was after several years of non-blooms for each one; it's not like I just got mad and ripped it out, lol. I just figured after 4 or 5 years the plant was weak (because again, I could never see any pest on it).

Do you - or anyone - know of any other way to treat this pest? I don't want to bother with monarda if I am going to lose the first round of blooms every year. I did a google search but amazingly little showed up in a search. I do garden organically, but I wonder if an insectidicidal soap would work as a preventive measure...?

Dee

I am thinking of ripping up all my monarda too because of the caterpillars. They are in virtually every blossom. My hummingbirds will miss the flowers but they look so awful...

Sorry to hear about your Monarda. I would be very bummed not to have the gorgeous patches that are blooming now. I am now seeing not one, but two hummers having aerial fights around the red Monarda.

I wouldn't rip them out, just give them a trim and get rid of all the flowers. They might rebloom. You could probably use BT to control the caterpillars, perhaps spray when the flowers are budding? I don't think the BT will bother the hummers or bees.

Bummer. I wish there was something else besides just cutting them back. I've been trying to grow monarda for about 6 or 7 years now and haven't gotten a single decent bloom out of any of them.

I guess I'll cut them back for now, and maybe enjoy a second bloom (well, technically it would be a FIRST bloom, lol) but if this happens yet again I will reconsider trying to grow these. But before I do any ripping I'll do a bit more research to see how to control these critters!

Dee

I normally get out there with a tweezer and removed them as soon as I see them. They're white, sometimes small, sometimes fat and plump! Lost plenty of blooms, but eventually just cut them off and will hope for a rebloom. They seem to like my Jacob Cline the most, but have seen some on the Marshall's; I have another darker pink that I don't know the name of that seems unscathed.

This is my grossest encounter:
{{gwi:235539}}

I've been having the same problem for the last 3 years. I'm happy to find out what they are. I picked a lot of them out and about half of the monarda is normal. Do you think spraying with BT at this point is worth it? Does anyone know how the eggs get inside the bud?

It's a good thing I read this post yesterday because I found a few caterpillars on my monarda 'purple rooster' last evening! I couldn't believe it! What next? I've never had these before!
I cut them back and will try Bt if there is further need.

Thanks for the great info a2zmom from NJ!

Well now you guys have me really worried. I have always enjoyed the Monarda blooms and the fact that without fail the hummingbirds appear to enjoy them.

Here's my patches this year in the "hummingbird garden". Red Noid and 'Raspberry Wine'. There is also quite a bit of Lobelia cardinalis and a sweep of Salvia in this garden, but they haven't started blooming yet.
{{gwi:248332}}

Terrene, I think you just posted this photo somewhere else, didn't you? I ask because I'm pretty sure it was this photo that I just saw, and my first thought was darn! why doesn't my monarda look like that? She obviously is not having the problem I just posted about! LOL

This worm has been in my yard since the get-go. I have never ever had decent looking monarda blooms, and I've tried it three times over the course of six or seven years. Actually, I just remember I started with some red monarda well over ten years ago that never throve either.

I'm going to cut the monarda back tomorrow and hope for some blooms, but I do hope to find some kind of preventive treatment so next year I can (finally, after all these years!) enjoy the first bloom! Or any bloom, for that matter!

:)
Dee

Hi Dee, yeah I posted that pic on the NEG forum.

Well I just went out a took a look at some of the flower heads that don't look so good. Guess what, found some of those gross little white worms! They look like maggots or something. There is also frass in the flower head. Not all the flowers but some. Hmmmm. Where did this bug come from?

The Monarda is still pretty, as much as possible during a very dry and hot spell with a few worms, and there are lots of bees, hummingbird moths, and a couple hummers on the flowers.

Based on my experience, soome years seem to be much worse than others. Last year, I didn't have any problem at all for example.

I wish some research was being done on this pest. Assuming it is Pyrausta signatalis (the horsemint moth), it's a night flying moth, so you are unlikely to see it. I assume the eggs are laid in the buds as they start to form, but I don't know for sure.

I'm not sure BT would work because I'm not sure it would be able to get inside the bud in the early stages of development.

It does seem like there's always some disaster ready to take down my plants.

Ugh...where have I been for this thread.

Thanks, Dee, for posting this. This is my first group of monarda. They proliferate quite nicely and are easily over 3 ft tall (my dog's fence is 36 inches and the monardas top that easily). Each plant also grew a bunch of lateral stems. However, the flowers were looking 'off' and I didn't know why. I thought my gardening skills were to blame. Then, I saw these creatures that look like big maggots. I had no idea they were responsible for my sorry looking monarda. I tried taking pictures but the focus was so off that I didn't think anyone would be able to ID the critters.

Thanks, tracey, for getting a picture.

Dee, I did a quick search and did not find preventative suggestions...besides sacrificing the blooms. If you find any, please share.

Thanks,
Tina

No, Tina, I didn't find many solutions either - I didn't find much info at all on this, period!

I'm guessing this is what has sabotaged my monarda-growing efforts for the last 7 or 8 years, but on the bright side, at least now I know it's not my lack of skills! Just maybe my lack of good eyesight, lol, as I had the darndest time finding these suckers. I never saw them in all the years of growing monarda, and even with this clump, after knowing what to look for, I had to look four or five times before I found something.

Here's to a second flush for all of us!
Dee

Dee, there seems to be no info on this pest at all. I took a deformed blossom to mu county extension office, but so far they've been no help at all.

a2zmom, you are right - when I did a google search on this I got about 5 hits total, and most of them had to do with the plant and not the worm. Funny, since it seems many people have this problem.

Maybe I'll try our extension office here...

Dee

Just stumbling upon this thread now and wished I had found it a few years ago! :) I'm wondering, now that 5 years have past, if anyone found a preventative solution? I was thinking about using netting in the spring, while the blooms are forming, to prevent the moths from laying, but wondering if anyone has found any other solution?

Thanks!!!! Feeling a bit of relief just identifying the little crappers.

Lara, I still haven't found any solutions other than hand picking the caterpillars Years with a really bad infestation, I cut the plant down to the ground and toss it all. It seems to ebb and flow from year to years..

I actually ended up losing that clump of monarda I posted about. It dwindled and then disappeared. I have another pot of monarda ready to plant (can't remember what variety I bought) so I will try again next season. I have not had much time this year or last to tend to the garden; hoping to be more hands-on next year and will keep an eye on this. Still not finding any info on how to deal with this pest, unfortunately.

Dee

What a mystery! Even my local nursery is stumped by this. I appreciate your updates just the same.

Updating this thread because, well, here we go again lol. That pot of monarda I mentioned three yeas ago? I planted it that fall. I had two years of some growth and a couple of decent blooms, so I was encouraged.

This season it's taking off and growing great and I was so excited to finally have a beautiful flush... and today, after looking at those brown, ratty, non-blooms, sure enough, there is the darn caterpillar. I searched to see if there was any new information/treatment, and one of the first hits of my search was this thread lol. So, I guess the answer is no, there are no new treatments.

I'll cut everything back and then I do think I will remove this in the fall. Just not worth not only the trouble, but the dashed hopes, dreams and expectations hahaha. This was supposed to be a focal point in my red/yellow/orange bed but I'll have to find something else I guess.

:)

Dee

^^ Oh, that's disappointing. I have the flamin' scarlet red "Jacob Cline" in the front, and while the foliage gets on my nerves (mildew and all) -- those flowers! Fortunately it's in a spot where I can see the flowers from the window and when I pull into the drive, but the foliage is out of sight enough that I don't go on a shovel-pruning rampage.

Fortunately, no caterpillars -- YET. But I never saw red lily beetles before this year, so it's probably only a matter of time. I wonder if they go after wild bergamot? I put that in last year and enjoyed the blooms (again -- foliage out of sight...).

mxk, I *think* I have Jacob Cline as well - will have to check the tag.

In the few days since posting I've already relented and decided maybe I WON'T rip out the monarda. More blooms have opened and they don't look half bad. Perhaps if I can remember to get out there and cut it back a bit to delay bloom next year, I'll miss the caterpillars.

Unfortunately for aesthetics, a Queen Anne's Lace (actually a Dara) decided to reseed right in the middle of the monarda. But the QAL is so gorgeous, so tall and stately and sturdy, and the blooms so big, I don't have the heart to yank it. I'm going to call it the cottage look. Yeah, that's it....

:)

Dee

^^ The monarda look good! I wouldn't pull them if you don't mind the preventive maintenance.

I love Queen Anne's Lace. I know people scoff and say it's a weed, but I think it's beautiful and a host plant for swallowtails. I have a lot of it growing along the outside perimeter of my vegetable garden fence, I just leave it alone and let it do its thing. I do pull any that crops up in the vegetable garden, though.

I adore QAL, mxk! I don't understand why people do indeed scoff and call it a weed. I think it's a very elegant bloom. I let mine reseed as well, and last year (two years ago?) started some Dara which comes in lovely shades of pink/maroon/burgundy.

I haven't gotten any really dark blooms this year but they'll come I'm sure. I had some dark maroon ones last year that were beautiful!

I just need to move them away from the monarda lol!

:)

Dee

^^That's different! I've never seen a QAL that wasn't white.

Technically Dara is daucus carota and QAL is ammi majus but I think they are related. I was also dismayed to read recently daucus carota may be invasive, so I have to look into that further. I may have to rip all mine out, which would be a disappointment!

:)

Dee