You might be noticing powdery mildew (a disease that causes a grayish, powdery film on leaves) in your garden. Common plants that could be affected are lilacs, phlox, bee balm, zinnias and nannyberry ...

“My red rhododendron looks as if it has a layer of ash or white powder on it (above). What should I do?” asks Birds & Blooms reader Steven Graves of Aptos, California. Horticultural expert Melinda ...

Powdery mildew appears as white or gray spots on roses, usually during warm, humid conditions. Catching infections early is key to stopping them from spreading by removing diseased parts and applying ...

Powdery mildew is a fungal disease affecting many plants, causing a white or gray coating on leaves and slowing growth. The fungus thrives in warm, dry weather with high humidity, especially in ...