Marianne's Response

Roses with holes

I have multiple roses bushes suffering due to them having holes all over their leaves. The occurrence has just started only years ago, but the roses are almost a decade old. A few are knockout roses and the other are unknown since it has been so long. In the past winter, I read that pruning them will encourage their grow in spring, so I proceeded to do so. They did exceptional this spring and their leaves didn’t have any holes. It wasn’t until late May they started accumulating the holes. I used the neem oil treatment on multiple occasions but, it doesn’t seem to work effectively. Do you know what could be hurting them?

Posted by Bryce Thomas on July 5, 2018

Marianne's Response

My roses also had this same problem this month. It took a close look at the back of the foliage to find a small green worm. There are several types of caterpillars that love roses and the young larvae are most active in mid summer so that is why you are noticing so much damage. Try using a spray with Bt (Bacillus thunringensis) following the instructions on the label. Good clean up around the base of the plant will help to control the pests from overwintering near your roses. Keep growing, Marianne Binetti

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