It is most prevalent in cooler temperatures and high humidity. Crowded plants and lack of air circulation are factors in the development of the disease. In Minnesota, increased levels of powdery mildew occur in the Spring and again in the Fall. To help control it, water before noon and avoid wetting the foliage. When powdery mildew is diagnosed early, control can be achieved by using a fungicide spray, such as Funginex, Benomyl, or sulfur.
Fungicides prevent infections from occurring and stop the spread of existing infections.
However, they cannot repair the damage that has resulted from powdery mildew. Be sure to read the entire label and follow directions carefully for proper application. Inc. All rights reserved.