Dogwood plant disease

Asked August 1, 2015, 2:44 PM EDT

The leaves of the dogwood plant have brown splotches on them. There are also a few whitish webs on some of the leaves but could not photograph them well. How should I treat and prevent?

Fairfax County Virginia

1 Response

The leaves in the photos show powdery mildew, a fungal disease. Older infected leaves can develop purple blotches that progress to dead areas. See our publication on management and control. The best recommendation is to plant powdery mildew resistant varieties in the future. Pruning for air circulation may help. You will have to monitor the plant in the future and decide if you want to spray fungicides or horticultural oil products listed for powdery mildew. This disease does not kill the plant but can weaken it. http://extension.umd.edu/sites/default/files/_images/programs/hgic/Publications/HG12_IPM_Series_Dogw...
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