Heavy leaf loss is common. Start sprays as soon as the first spots appear. Continue sprays at 7-day intervals as long as the disease threatens to spread. Do not apply chlorothalonil within 7 days of harvest, and do not graze treated area or feed treated plant parts to livestock. The fungus that causes powdery mildew appears as white to gray powdery patches on leaves, stems and buds.
Many leaves curl and become distorted.
The fungus spreads from plant to plant by windborne spores. Warm days and cool nights contribute to its spread. Control by dusting or spraying with sulfur when the fungus first appears. Repeat at 7 to 10-day intervals as long as the disease threatens to spread. Do not use sulfur at blossom time.