Violet Bramble Rust, this rust fungus thrives on blackberries in wet and cool summers.
Also known as:
Black
Violet Bramble Rust (Phragmidium violaceum). This rust fungus thrives in wet and cool summers. The fungus overwinters on affected leaves.
Violet Bramble Rust (Phragmidium violaceum) is related to Rose rust (Phragmidium mucronatum).
Where to find
Control
Remove infested leaves and dispose of them (not in the compost pile).
Prevention
Prevent rust by ensuring good air circulation around and the blackberry and raspberry bushes.
Remove fallen leaves in the fall and dispose of them (not in the compost pile).
