Causal Agent

Xanthomonas campestris pv. hederae. 

 

Hosts

English Ivy. 

 

Symptoms

The bacteria may enter the Ivy through natural openings and/or wounds. Older leaves will develop light green, watersoaked spots that later turn dark brown to black, circular to irregular in shape. The bacteria can potentially move into the stems, causing them to shrivel and darken, which in turn leads to branch dieback.

 

Control

Remove and destroy symptomatic leaves and twigs. Plants should be watered early in the day, allowing the leaves to dry in the day. If possible, watering from the surface or subsurface is encouraged. Beds should be cleared of old leaves and debris each spring. A copper-based fungicide such as Bordeaux mixture may be applied. This treatment, however, may be ineffective on fungal leaf spots. Thus it is best to be certain of the causal organism involved. Please contact your local county extension office for current information.