Avoid infested soil. No chemical control is listed. Rose anthracnose causes purplish brown, circular, one- half inch leaf spots. The center of the spot turns gray and drops out. Black spot sprays generally control this disease.
Black spot causes black spots on the leaves.
The leaves turn yellow and drop. Remove and destroy fallen infected leaves. Use Funginex, sulfur, chlorothalonil or basic copper sulfate to control this disease. Botrytis blight causes flower buds to turn brown and decay. The petals of unopened flower buds are easily lifted off the stem.