What's this white powder all over my violet (powdery mildew)?
Powdery mildew looks like a fine white powder on the leaves and flowers. It's easily disturbed by blowing on it. Powdery Mildew is caused by a fungus, which likes sudden changes in temperature and poor air circulation. In addition to being unsightly, powdery mildew will mar flowers and leaves -- and eventually kill your plant.
First, isolate any affected plant. The most effective treatment of powdery mildew on African violets is Green Light Fung-Away. It does not harm either the flowers or the leaves. Remove plants from lighted areas when spraying and wait until they dry to put them back. Make sure to spray the entire plant -- don't miss any spots! Green Light Fung Away can be found in garden centers or online.
Lysol will help control powdery mildew but it's not nearly as effective as Fung-Away. Lysol also damages the flowers so it's best to disbud your violet before spraying. Once again, remove the plants from the light and wait until they dry to put them back. Hold the aerosol can about 12 inches from the plants and let the spray fall on them. Don't spray it directly on the plants because the Lysol is very cold when it comes out of the can. You'll probably need to spray repeatedly.
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