Black Spot Defoliation on Roses in Kentucky: Identification and Treatment

A rose bush in south-central Kentucky lost leaves that had black spots and appeared eaten. The plant looked terrible.

Classic Black Spot

The symptoms are textbook black spot (Diplocarpon rosae), a fungal disease. The "eaten" look is likely the spots coalescing and tissue dying, not insect feeding.

Treatment

Apply a rose fungicide specifically for black spot. Never spray in high heat. If insects are also present, use a combination fungicide/insecticide product. Remove and destroy fallen leaves to reduce reinfection.