Euonymus powdery mildew

Symptoms

A white to greyish, powdery or felt-like fungal coating develops on the leaves of Euonymus japonicus, typically starting on the upper surface and on the soft new shoots, then spreading to cover whole leaves and green stems. The bloom wipes off with a finger, distinguishing it from surface dust or scale. Heavily infected young leaves become distorted, crinkled, cupped or stunted, sometimes with yellowish or reddish-purple blotches, and may drop early. On this evergreen hedge the disease is most conspicuous on the flush of tender spring and autumn growth, leaving the bush dull, greyed and disfigured.

Plants affected

• Japanese spindle

Common questions

How do I recognise Euonymus powdery mildew on Japanese spindle?

A white to greyish, powdery or felt-like fungal coating develops on the leaves of Euonymus japonicus, typically starting on the upper surface and on the soft new shoots, then spreading to cover whole leaves and green stems. The bloom wipes off with a finger, distinguishing it from surface dust or scale.

Do I have to report Euonymus powdery mildew?

No. Euonymus powdery mildew is not a notifiable organism, so there is nothing to report to an authority. Treat it as a normal garden problem.

How is Euonymus powdery mildew treated?

Mainly with biological and cultural measures — removing affected material, changing the conditions that favour it, and treating with agents approved in your country. The exact steps and their timing depend on the plant, the season and where you live: Dr. Phyto works them out in a free diagnosis.