Powdery mildew is the most frequent fungal infection affecting hops. It is spread via fungal spores. Where the spores land on the leaves, the leaves at first show a lightening in color. On the underside of the leaves, a carpet of grey fungus develops. The flowers harden and do not develop, the cones turn a mottled brown.
The peronospora alert service in the growing regions makes it possible to fight the infection in a targeted manner. Information is provided daily about any possible risk of infection by analysing sporulation, leaf humidity and the air saturation deficit.