Cucumber Beetles Attacking my fall mums

Asked October 26, 2019, 4:22 PM EDT

Hi Expert! This is the second year that what I think is cucumber beetles attacking my fall mums. Anything I can do about it? They munch off the petals. Marge Spears

Berrien County Michigan

3 Responses

Unusual if indeed it is cucumber beetles attacking your mums Marge. If so, they are brightly colored and easy to identify. They are not a pest usually seen on mums however. Read more here:
https://www.canr.msu.edu/uploads/files/MSUE_PDFs/updated_cucumber_beetle_2017.pdf

For controlling cucumber beetles Organically:
https://www.highmowingseeds.com/blog/organic-control-measures-for-striped-cucumber-beetles/

Otherwise, mums, usually reliably beautiful in fall, are actually targets for a number of pests and diseases. Read more here:
https://hgic.clemson.edu/factsheet/chrysanthemum-diseases-insect-pests/

And here: https://www.canr.msu.edu/news/scout_garden_mums_for_insect_pests_to_avoid_surprises

Herbaceous plants that die back to the ground each year, they should come up just fine for you come spring, unless wilt or some other affliction gets transferred to them by the insect feeding. That said, a positive ID is required before considering treatment options.

Good luck Marge!

Hi John, Apparently the pictures I uploaded didn't come through. I will try again and you can tell me your opinion as to identification.

Thanks,

Marge

No doubt about it this time Marge. Easily identifiable spotted cucumber beetle it is. If they were there, I couldn't see any on the first pic. Spotteds are considerably less of a problem to our region, flourishing more in the south, while the striped are more common here. Except that spotteds are indeed a problem for you currently. Answering some 300 questions per year since A an E program began in 2011, I've never had a question such as this. It is what it is however and because this is now the second season you have had this problem, I would consider doing something about it. Read more here in depth about spotted cucumber beetle: http://entnemdept.ufl.edu/creatures/VEG/BEAN/spotted_cucumber_beetle.htm#desc

Not one ever to use anything stronger than insecticidal soaps or dormant oils in my landscapes, I am intrigued by the writeup for kaolin clay, mixed with water and used as a spray to confuse cucumber beetles and others organically seemingly without collateral damage. Read more here: https://sites.lafayette.edu/lafarmblog/2015/07/29/kaolin-clay/

Pyrethrum/pyrethrin sprays are also favored, organic because they are derived from dried daisy flowers. They are however highly toxic to a number of insects including bees and wasps so you wouldn’t want to use it when they are flying. Pyrethrum sprays are favored by vegetable growers because they are deemed harmless to humans and they break down quickly, within days. So, it’s your call and again, good luck Marge!