Black-eyed Susan – Flower Petals Disappear

Q: My black-eyed Susans were beautiful last year, but this year the growth is stunted by a very small black beetle. It eats the upper bud and leaves. What organic insecticide can I use to eliminate this pest?

A: I noticed the same creature on my black-eyed Susan’s a couple of years ago. Your description is exactly right: the beetle completely consumes the flower petals, leaving just a deformed knob.

I don’t think the beetle has a common name. I call mine “Susie beetles”.

Spinosad is considered an organic insecticide and it will kill the beetles handily. Spray now (July) and once again in two weeks. Next year spray a couple of times, starting in early May.

Otherwise, any garden insecticide will kill them, using the schedule above.