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Keyword Search Results for:
Grayish-White Dust

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Question: 164-5201
My Gaillardia has some grayish-white dust on the leaves. Should I spray it and with what? Joyce, Harve de Grace, MD

Mort's Answer:
Your Gaillardia should survive this weird weather that had been causing havoc with plants on the east coast. My phlox developed mildew this summer because of the stress that they suffered from the lack of rain last month. Now the wet weather is spreading the mildew. Powdery mildew can be treated with Bordeaux Mix. Since perennial G. aristata has already bloomed, it not necessary to spray. Annual G. amblyodon and G. pulchella are going to die in the fall. It is not going to help the annuals at this point. If the powdery mildew occurs again next year, then I would use the fungicide.

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