It’s August and that means humidity. The combination of high humidity, occasional rain, plant crowding and poor air circulation develops a fungus among us….powdery mildew. These conditions cause spores to spread and develop a whitish grey powdery cast on foliage. It can happen to many different plants although some are more susceptible than others.
Lilacs, Monarda, Zinnias, Phlox, Dogwoods, Cucumbers and even lawns can fall prey to this fungal condition in August. Don’t be a “spore” loser. Powdery mildew is rarely fatal but does stress and weaken plants, inhibits photosynthesis and is unsightly or should I say leaves your plants looking in “spore” taste. Fight back by possibly thinning or staking some plants to improve air movement. If you’re irrigating over the top, water in the morning so the foliage can quickly dry as the sun comes up. It’s best to water at the base of plants when possible. Once you’ve changed the conditions the plants are growing in you may wish to use a fungicide when necessary. I like to use a Copper fungicide or Sulfur fungicide. They can be mixed with water and applied with a sprayer or applied as a dust. Just see what my well grounded advice “mildew” for you! Powdery mildew is something the weather tends to do to us in August but you don’t have to “sulfur” alone.