Powdery mildew: how to spot, prevent and treat it disease

How do you spot powdery mildew?

A white, floury coating spreads over the leaves, first on the lower and older ones. The leaf under it yellows and dries up. The fruit stays small, because the plant loses leaf surface.

How do you prevent powdery mildew?

Plant resistant varieties, leave an airy spacing and sun, and clear the debris at the end of the season. Unlike most fungi it is not helped by wet foliage, since it spreads in heat and high air humidity, in a dry summer too.

What works against powdery mildew?

Oil products meant for powdery mildew on the squash family work on contact. They do not cure a leaf that is already affected, but they stop the spread to healthy ones. On herbs cut the affected shoots back instead, since the new growth comes clean. On ornamental perennials what is left is spacing and moisture.

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Which plants get powdery mildew? 36

Vegetables 7

Herbs 3

Fruit trees 2

Berries 1

Ornamentals 23