Because the fungus survives from year to year in infected material, remove infected material by raking and destroying fallen leaves. Prune out any canes that have the symptoms of blackspot disease. Apply a fungicide registered for use on roses to control black spot. Begin applying the fungicide in the spring as daily temperatures reach the high 50oF range and repeat every 7-10 days to protect newly emerging foliage. Spraying may be omitted during hot, dry spells in summer.
Resistant varieties are available.
Based on material developed in 1992. Lawrence K. Forcier, Director, University of Vermont Extension, Burlington, Vermont. University of Vermont Extension and U.S. Department of Agriculture, cooperating, offer education and employment to everyone without regard to race, color, national origin, sex, religion, age, disability, political beliefs, and marital or familial status. Last reviewed April 24, 1998.