Brown spot on bottom of green peppers - and white substance on cucumber leaves. Help!

Asked August 6, 2016, 9:45 AM EDT

Why are my green peppers turning brown on the bottom (first picture)? And my cucumber leaves are suddenly covered with a white substance and drying out (second and third pictures)? Both plants were planted in early May and are in the sun most of the day. Both are yielding peppers and cucumbers, respectively. The cucumber leaves look like they are dying and I fear the cucumbers will vanish. The peppers started with the spots about 2 1/2 weeks ago and the cucumber plants about 2 weeks ago. No pesticides on anything. I really need your help and advice. Thank you so much!

Baltimore County Maryland cucumbers vegetables peppers powdery mildew fungal diseases

1 Response

The spots on the pepper look fungal in nature, especially the fuzz. Several fungal and bacterial disease can affect peppers. It has been hot, humid, with a lot of moisture. Conditions are perfect for disease. We recommend picking the fruits and discarding. Make sure the plants get plenty of air circulation and are supported with cages or trellises, and mulched. See our vegetable profile on peppers http://extension.umd.edu/growit/vegetable-profiles-peppers
http://extension.umd.edu/sites/default/files/_images/programs/hgic/Publications/HG57%20IPM%20Peppers...

Your cucumbers have powdery mildew, a fungal disease. Cucumber is a common host plant. This fungal disease is favored by warm weather and can be destructive in dry as well as hot seasons. Infections often start when plants are mature and are rarely a problem for gardeners. No control is recommended. Cucumbers produce for about 4-5 weeks and decline. Next season you may want to plant two crops - an early and later crop and keep evenly watered around the base of the plant. Monitor throughout the season. Here is our profile on cucumbers http://extension.umd.edu/growit/vegetable-profiles-cucumbers


Please refer to the disease resistant list from Cornell for powdery mildew resistant varieties http://vegetablemdonline.ppath.cornell.edu/Tables/TableList.htm
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