Forsythia Gall Disease (Phomopsis): Pruning and Sanitation

Large, beautiful forsythia has galls on most branches. Can recurrence be prevented?

Cause

Phomopsis fungus – no chemical control.

Management

• Prune infected stems during dry weather.
• Disinfect pruners between EVERY cut (1:9 bleach:water).
• Discard infected material in trash (not compost).
• Rake all debris under plant at season end.
• Do not replant forsythia in same spot if removed.

Promote Vigor

Regular watering and fertilizing help plant tolerate infection. Some recover with good care.