Box blight (also known as boxwood leaf drop) was first found in the UK around 1990. Since then it has been found throughout Europe and as far away as New Zealand, Ohio, Oregon, Pennsylvania, New York and British Columbia to name a few places.  There are two types of organisms which can cause box blight and they can both occur at the same time. Volutella buxi which is the asexual stage of the fungus Pseudonectria rousseliana and the fungus Cylindrocladium buxicola that produces symptoms similar to Volutella.

Volutella buxi results in browning of the leaves leaving bare patches in topiary and hedges. It can spread in wet conditions with a  pinkish spore appearing on the undersides of leaves. Fallen leaves can carry the disease through the winter months and new spores are produced in the spring. They can enter the plant through damage to leaves, stems and clipping cuts.

Cylindrocladium buxicola is the more serious of the two and this causes leaves to develop dark brown spots which enlarge and patches of grayish fungal growth appear on the underside of the leaves which release the infection. This form of infection can penetrate the cuticle of the leaves meaning infection can occur and spread easily.


Last modified on Wednesday, 19 March 2014