The common diseases that can affect your pumpkin are; anthracnose, powdery mildew, scab and gummy stem. It caused by bacteria that is responsible for the yellowish spots around the leaves and the ...

To reduce problems with powdery mildew and other fungal diseases, provide adequate air circulation, avoid overwatering, spray milk on plants and/or treat plants with Serenade (Bacillus subtilis).

Some plants that are particularly vulnerable to powdery mildew infections include crab apples, lilacs, bee balm, roses, ...