How to Solve a Powdery Mildew Problem
- 1). Apply a fungicide as soon as you notice white patches or other signs of the disease, as control is difficult when the powdery mildew is extensive. Use the fungicide as directed on the label and apply it regularly. Affected plants will need more fungicide during damp, cool weather. Cover the top and bottom of leaves and all affected stems and foliage. Non-toxic fungicides are available for indoor plants, vegetable plants and fruit trees.
- 2). Clean up the area around the infected plants. Remove any dead foliage, leaves or other debris. Prune away any infected plant parts and dispose of them in a sealed bag to prevent spread of the fungus.
- 3). Move plants to a location where the plants will be exposed to at least six hours of sunlight per day, if possible. Plants in damp, shady locations will be more susceptible to powdery mildew. Allow space between plants so that each plant will have good air circulation. Prune or remove crowded plants.
- 4). Weed or prune affected plants when the foliage and soil are dry. Avoid handling your plants when the foliage is wet, as handling wet plants can spread the disease to unaffected plants.
- 5). Water plants in morning or early afternoon so the plants have time to dry before evening. Water at the base of the plant to keep the foliage dry. Water the plant deeply, then allow the soil to dry slightly before watering again. Don't allow soil to remain damp and soggy.
- 6). Feed affected plants with a slow-release fertilizer and don't feed affected plants after early August. New growth is more susceptible to powdery mildew.
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