Euonymus: Bacterial blight
categories: Euonymus Euonymus Diseases Ornamentals Shrubs
revision date: 2022-12-05 12:00
Biology
Bacterial blight causes shoots to blacken and die back. Leaf spotting caused by the blight is infrequent on euonymus, but common on other plant species. Infection is favored by moist weather. Wounds are frequent infection sites, especially those caused by frost damage. The bacterium which causes the blight is easily spread by splashing water, wind, insects, and contaminated pruning tools. Bacterial blight is also common on lilac, maple, cherry, and many other woody plants.
Management Options
Use Integrated Pest Management (IPM) for successful plant problem management.
Non-chemical Management
Select non-chemical management options as your first choice!
- Avoid overhead irrigation.
- Prune and destroy infected tissues as soon as they are noticed. Make cuts well below infected tissues and sterilize pruning tools between cuts.
- Provide proper plant culture. Healthy plants are more resistant to infection.
- Protect plants from frost damage.
- Space plants properly and prune to improve air circulation.
- Avoid wounding plants during periods of moist weather.
Chemical Management
IMPORTANT: Visit Home and Garden Fact Sheets for more information on using pesticides.
Apply when leaves drop in fall (deciduous euonymus) and during wet spring weather. Note: These fungicides can be damaging to plant tissue, so apply only under fast-drying conditions. Homeowners should not make foliar applications to trees over 10 ft tall. Consult a commercial pesticide applicator for treatment of trees and shrubs over 10 ft. tall.
Approved Pesticides
Listed below are examples of pesticides that are legal in Washington. Always read and follow all label directions.