BLACK SPOT is a fungal disease that causes circular black spots on the surface of leaves during spring and early summer. The leaf eventually turns yellow and drops off prematurely.
   
BLACK SPOT CONTROL OPTIONS
There are usually several management options for solving any pest or disease problem. Use the non-pesticide approach whenever possible, saving pesticide use as the last line of defense. If a pest is identified at a damaging level, select a control targeted to the problem. This is called "Integrated Pest Management" or "IPM".

GROWING HEALTHY ROSES
Buy disease-resistant roses and plant in full sun. Prune to remove dead or diseased plant material. Water at the base of the plant to avoid wet leaves which foster fungal diseases. Roses prefer well-drained soil, rich in organic matter. Provide a gradual supply of slow-release nutrients.

Monitoring and early intervention is the key to controlling black spot. Do not plant roses close together. Prune leaves and stems to create air circulation Pick infected leaves off the plant and the ground, and discard in trash (do not compost). Wash hands with soap and water.

ALTERNATIVE CONTROLS
Product options include: fungicidal soap (formulated for black spot); soap formulations with sulphur; and soap formulations with copper. Apply to tops and under side of leaves. Reapply after rain.

CHEMICAL CONTROLS
If you have decided to use a chemical fungicide treatment, read the precautionary statements on the label before making your selection.
READ THE LABEL BEFORE BUYING ANY PESTICIDE.
Re-read the label before using, storing or disposing of the pesticide — the label is the law. Following label instructions will help reduce risks to human health and the environment.
Sources of information:
Greg Patchan, Horticulture Agent, Oakland County MSU Extension.

Ellis and Bradley, Natural Insect and Disease Control, Rodale Press

Olkowski, et. al., Common-Sense Pest Control, Taunton Press

FOR ADDITIONAL INFORMATION:
Oakland County Garden Hotline:248/858-0902

National Pesticide Telecommunications Network (NPTN):1-800-858-7378
(Information about environmental and health effects of specific chemicals)

Household pesticide disposal: If you live in one of the SOCRRA communities, call for an appointment:248/288-5153
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