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Good day, what could be the white powdery substance I have on a red leaf dahlia, it comes off when wiped, but there are too many leaves to wipe. I have several of these dahlias but only 1 is affected. Any ideas as to what it is and what can I do ?



Sounds like mildew. Spray with a fungicide and make sure the plant has enough water.

4 Sep, 2016


Yes, it's Powdery Mildew. Dahlias are prone to it. Although it doesn't look nice, it won't do the plant any harm.

4 Sep, 2016


Thankyou for your replys. Glad it will do the plant no harm as they are lovely.

4 Sep, 2016

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