Last
summer many of my plants and shrubs were attacked by powdery mildew. We have pets and do not want to use
chemicals.
In general plants grown in
full sun with good air circulation (properly spaced and thinned) have fewer
mildew problems. Drought stressed and overfertilized plants are more likely to
develop the problem. Excess
fertilization produces an abundance of lush succulent growth that is more
susceptible to this disease. Susceptible plants such as zinnia, garden phlox
and lilacs can get mildew even in good growing conditions. Plant mildew resistant varieties
whenever possible. Remove infested
foliage during your fall cleanup to reduce the amount of overwintering
fungus. Neem and some other
eco-friendly fungicides can help reduce powdery mildew. Just be aware you will
need to make regular applications at the first sign of the disease and
throughout the remainder of the growing season.