Answer: I'm afraid your question wasn't very specific so I can't provide a specific answer. If you're talking about algae and moss on the soil surface of your flower beds, it's an indication of poor drainage, low fertility and too much shade; if you're talking about powdery mildew (a common late season malady), prune the plants back to increase air circulation and to remove the pathogens. Depending upon which plants you're growing, you may be able to use a preventative spray. Submit a new question to this forum with more details and we will be able to give you more specific information.
Best wishes with your garden.
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