DiseasehighApr–Oct

Phytophthora root and shoot rot

Phytophthora spp.

This description was machine-translated.

How to spot it

Phytophthora root and shoot rot is caused by soil borne fungi of the genus Phytophthora, which become active above all where there is waterlogging. Affected plants wilt despite moist soil, leaves turn pale or reddish and individual shoots die back. At the root collar, once exposed, a dark, pulpy bark shows with a sharp boundary to the healthy wood. Without countermeasures the whole plant can die within a few weeks.

Prevention

The most important thing is a free draining site without waterlogging: loosen heavy soils with sand or compost and, if needed, create raised beds or drainage. Never plant too deep and do not heap soil or mulch against the root collar, so that the bark stays dry. Remove infected plants together with their root balls early and do not replant in the same spot, since the pathogens remain in the soil. For new plantings choose tough, more resistant varieties and water at the base rather than over the leaves, in order to keep the bark at the base of the trunk dry.