False Mildew
Peronosporaceae
This description was machine-translated.
How to spot it
You will find that the False Mildew is not a true fungus, but an oomycete that comes from the underside of the leaf, unlike the True Mildew. On the upper side you see yellow‑square spots, below a gray‑violet coating. On cucumber, onion and lettuce it can collapse entire stands within a few days once it is wet and warm.
Prevention
Water in the morning and only at the roots, so that the leaves dry by evening. Keep generous plant spacing for good airflow and choose resistant varieties such as cucumber Saladin. Remove infected leaves immediately and do not put them on the compost.
Affected plants
These plants in our database are especially susceptible.
Good Henry
Blitum bonus-henricus
moderately susceptibleWild rocket
Diplotaxis tenuifolia
moderately susceptibleRed Dock
Rumex sanguineus
slightly susceptibleCorn salad
Valerianella locusta
Cucumber
Cucumis sativus
Head lettuce
Lactuca sativa
Onion
Allium cepa
Red Onion
Allium cepa 'Red'
leaf lettuce
Lactuca sativa var. capitata
pickling cucumber
Cucumis sativus var. anguria
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