Rose Plant Diseases

Rose bushes can be a beautiful addition to a landscape; however, the diseases they may contract are not. Black spot, powdery mildew and rust are three common diseases of rose plants.

Types

Powdery mildew, rust, black spot and Botrytis blight are common diseases of rose plants.

Identification

Powdery mildew coats the leaves, stems and buds of a rose bush with a white powder-like substance. Rust appears as orange- or rust-colored growth on the underside of the leaves. Black spot appears as black marks. Botrytis blight makes the buds close up and droop.

Treatment

In most cases, fungicides can be used to treat diseases. For Botrytis cinerea, remove all drooping buds immediately.

Prevention/Solution

Many rose diseases can be prevented by planting plants in full sun, where any moisture on the leaves will quickly dry. In addition, a fungicide can be applied as a preventive measure.

Tips

Some varieties of roses are less susceptible to disease than others; when possible, purchase disease-resistant plants. Always follow the care instructions when planting roses in your garden.

References

• University of Minnesota Extension
• Ohio State University Extension