This formerly beautiful coreopsis that I raised from seed last year was nearly completely devoured by leaf beetle larvae. I don’t know enough about insects to identify which species of leaf beetle it is but I am positive it is a Calligrapha. The damage is pretty devastating. The leaves are spotted with holes and very few leaves have escaped untouched. The interesting thing (Yes, I can find something interesting in this!) is that they are only on the coreopsis plants. I have several of them in our rain garden along with other plants like coneflowers, goldenrod (Solidago), butterfly weed (Asclepias), and some ornamental grasses but only the coreopsis plants received any damage. The picture above was the worst one damaged but all of them have seen damage. Coreopsis are generally pest free but apparently I have managed to attract one of the few pests that like them.
So how do I know it’s The Beetles (and their larvae)? Take a closer look at the damage and you will see the culprit. The little black larvae on the left has been caught red handed, feasting on foliage. I had no choice but to bring out the insecticidal soap. Hopefully I managed to eliminate them all but I’ll treat again in a couple days. I would love to wait for a beneficial bug to find them but by that time my coreopsis would be gone. Insecticidal soap should do the trick! I sprayed each coreopsis on as much of the leaf surface as I could making sure that the undersides were covered.
Coreopsis is a vigorous grower and should come back as long as the larvae stay away. At least the other plants didn’t look as bad as this one. If you see even one of these little insects eliminate it fast and watch out for more! I’m definitely not a fan of these beetles!
Hi Dave,
I’m sorry to see all that damage, but I hope your plant can bounce back. Great photos of the beetles though!
Really gross! I do hope it bounces back.
That really stinks……hope the soap does the trick!
Arghhh, Dave! That is awful! We are having quite a bit of insect damage here too, is it all the rain? Or just food for the baby birds that are hatching all over? I have resisted spraying anything other than water on them, hoping the birds get it in gear, but would not hesitate to use the soap on damage such as yours. There was one of the deciduous azaleas that had many stripped leaves, luckily it is in an out of the way spot that I don’t look at all the time.
Frances
It’s all a part of the process Dave. No matter how we try to prevent it, bugs will invade. You might find some comfort in knowing that only about 3% of the entire insect population are considered to be pests. But then again, maybe you won’t find comfort; just looking at your poor coreopsis is enough to sadden any gardener. I’m preparing a bug talk for next month and reading things such as this will provide timely anecdotes, I might also ask to use one or two of your photos of this bug for my presentation. I’m pretty sure I don’t have pictures of this particular beetle. Let me know if that’d be okay via email.
Rain = lots of weeds and tall grass, but …I am now nervous to go out there and see what nasty critters might be dining on the flowering plants! Yikes…if it’s not one thing it’s another! Look for mosquitoes to be out soon. gail
These little buggers are gross! I have lily leaf bettles in my garden and their larvae is pretty gross too…. kind of looks like poop on the leafs! YUCK! –Jackie
I have had great success with insecticidal soap, but it’s devastating to find the problem this late.
I just discovered a slug on my first ripe strawberry and am off to buy some cheap beer to nip that problem in the bud!!
Nasty little critters Dave. Hope they go away. I think I had one of these last yr. but not on coreopsis as I didn’t have any of those.
Check your mail.