Issue with leaves on Ninebark shrub - Ask Extension
Farmington Hills. What or why are some of the leaves on my Ninebark turning white? It does not appear to be powdery mildew, cannot be rubbed off. Coul...
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Issue with leaves on Ninebark shrub #880497
Asked August 07, 2024, 9:17 AM EDT
Farmington Hills. What or why are some of the leaves on my Ninebark turning white? It does not appear to be powdery mildew, cannot be rubbed off. Could it be some kind of lichen? Should I remove those branches with the white tips?
Oakland County Michigan
Expert Response
Good Morning,
It certainly looks like powdery mildew. Most powdery mildew fungi are host-specific. You don’t need to worry about powdery mildew on ninebark (Podosphaera aphanis var. physocarpi) spreading to other plant species in the landscape.
To treat powdery mildew:
Remove infected plant material. Do not compost infected plant material. Increase air circulation by pruning nearby vegetation.
Powdery mildew on ninebark does not usually warrant the use of fungicides.
See attached for more information.
Home, Yard & Garden Newsletter at the University of Illinois
Powdery mildew on trees and shrubs | UMN Extension
P is for powdery mildew on ornamentals - MSU Extension
You can also send in a sample for a small fee to get a firm diagnosis.
Submit Samples - Plant & Pest Diagnostics (msu.edu)
I hope this helps. Thanks for using our service.
It certainly looks like powdery mildew. Most powdery mildew fungi are host-specific. You don’t need to worry about powdery mildew on ninebark (Podosphaera aphanis var. physocarpi) spreading to other plant species in the landscape.
To treat powdery mildew:
Remove infected plant material. Do not compost infected plant material. Increase air circulation by pruning nearby vegetation.
Powdery mildew on ninebark does not usually warrant the use of fungicides.
See attached for more information.
Home, Yard & Garden Newsletter at the University of Illinois
Powdery mildew on trees and shrubs | UMN Extension
P is for powdery mildew on ornamentals - MSU Extension
You can also send in a sample for a small fee to get a firm diagnosis.
Submit Samples - Plant & Pest Diagnostics (msu.edu)
I hope this helps. Thanks for using our service.
