Bacterial crown gall causes nodular growths along the stems that may kill them. Cut off and destroy infected canes, or destroy the entire plant if it's severely infected.
Several leaf spots may be seen but are not serious and can be controlled with sprays of basic copper sulfate.
Dieback occurs when a fungus enters the blossoms and flower stalks. Twigs on infected stems die back. Prune out and destroy dead twigs and stems. No chemical control is listed.
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