Powdery mildew is a gray, talcum powder-like coating that covers the leaves, flowers, and even fruit of some of your favorite summer vegetables, perennials, and shrubs. Powdery mildew can affect plants in all regions of North America.
Powdery mildew fungal spores are spread by wind and overwinter on plants, and in plant debris. Unlike mildews that appear in bathrooms or basements, powdery mildew does not need direct contact with water in order to grow. The warm days and cool nights of late summer create an ideal climate for spore growth and dispersal.
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