Ninebark Bushes

Asked July 25, 2020, 11:35 AM EDT

We have 6 Burgandy Wine Ninebark bushes that were planted about 8 years ago. They were doing great until this spring when I noticed white patches on most of them. What can I do to help them?

Wayne County Michigan

1 Response


Thank you for using the Ask an Expert service. Sorry for the slow response.

It looks like your ninebark plants have powdery mildew. It appears from the articles linked below that powdery mildew can be more of a problem for ninebark plants than some other plants. You might want to consider fungicide applications. Fungicide active ingredients that could be effective are mentioned in the articles. Always read and follow all label instructions when using pesticide products. The label is the law!

Powdery Mildew – Trees & Shrubs from U. of Wisconsin-Madison Extension

Powdery mildew on trees and shrubs from U. of Minnesota Extension

Ninebark (Physocarpus spp.)-Powdery Mildew from Pacific Northwest Pest Management Handbooks

Please let me know if you have further questions after reviewing the articles!