Answer: If the brown spots are on the undersides of the leaves, your azalea may be developing powdery mildew. If the brown spots are on the upper sides of the leaves, it could indicate a disease or the spots may be symptoms of insect feeding. Since we don't know for sure, you might just want to prune off the affected foliage. For a positive diagnosis, take some of the affected leaves (in a plastic baggie) to a well staffed nursery, a Master Gardener Clinic, or your local cooperative extension office. Good luck with your azaleas!
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