Dr. Phyto

common boxwood

Buxus sempervirens

Diseases & pests on this plant

• box blightCalonectria pseudonaviculata

  Dark brown circular spots on leaves with darker rings, black streaks on green stems (very diagnostic — bacterial diseases do not produce streaks), defoliation from base of plant upward leaving bare brown stems, white spore masses on leaf undersides in moist conditions, entire plants killed within 2-3 years.

• box tree mothCydalima perspectalis

  Green caterpillars with black stripes and black heads, inside dense white webbing, rapidly skeletonise and strip box (Buxus) leaves, then strip the green bark — a heavily attacked bush turns brown, webbed and skeletal within days; pale green-and-white moths with a brown wing border fly from spring to autumn over 2–3 generations. The webbing + green-striped caterpillars distinguish it from box blight (which is a leaf/stem fungus, no caterpillars).

• boxwood Volutella blightVolutella buxi

  Salmon-pink waxy spore cushions on leaf undersides + dead stems (the diagnostic feature distinguishing from Calonectria), bronze-colored leaves with curled edges, dieback of individual branches, blackening of stems but typically WITHOUT the dark streaks of box blight.

• longtailed mealybugPseudococcus longispinus

  White cottony masses with long fluffy tails on twigs and fruit, copious honeydew, sooty mould blackening leaves, distorted fruit when calyx end infested.