Recognising diseases and pests


How do you recognise mildew?

Powdery mildew weakens the plant by sucking sap from the leaf cells.

Under optimal conditions, this fungus can develop and spread at lightning speed. The optimal temperature is around 22°C with an RH of 60% – 80%. Under these conditions, the spores germinate within two hours.

Spores (or conidia) are the cause of the infestation. The spores germinate on the leaves and suck the sap from the leaf cells. Powdery mildew develops in the leaf cells, which serve as a source of nutrition for the development of the fungus.

The fungal threads arising during the germination process enable the spores to spread. This in turn enables the life cycle to continue for a long time. Powdery mildew can only develop on living material.