Time to act:
Jun, Jul, Aug
There are many different fungi that cause this problem, each of which usually affects a particular plant or group of plants. In each case they produce similar symptoms. Affected plants will have discoloured leaves, often also distorted when young, while general growth and vigour is poor. Also learn about powdery mildew on roses.
In summer, a white powdery coating covers the leaves and possibly the shoot tips and flowers too. Leaves may then become discoloured and distorted, with poor growth and even dieback.
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