When and in what conditions is Box Blight most likely to appear?
The key prerequisite for Box Blight to thrive is wet, or even just damp, conditions. It loves the rain. The other favoured factors are high humidity, shade and shelter (poor air circulation) – it has been noticed that Box planted in particularly windy locations are proving less susceptible. Unfortunately, and unlike some fungi, Box Blight is untroubled by the cold and can live through the severest of winters.
It will be no surprise that stressed, unhealthy plants are particularly susceptible to Box Blight – this, as we will see, at least offers gardeners a preventative strategy.
Box Blight is also patient –viable spores, at least a year old, have been found in soil, waiting for optimum conditions to return. And the mycelium, which produces the spores, can survive for up to six years on fallen foliage.
This means that while so many garden pests and diseases are associated with spring and summer, Box Blight’s most virulent time is autumn and winter – August onwards.