Answer: Black spot fungus of rose is everywhere. If you have roses, you will have some black spot. There are varieties that are resistant and seldom get black spot. When they do it is usually not a significant problem and seldom if ever requires a spray.
Most varieties however, must be sprayed on a regular basis to prevent black spot infections from becoming severe. In severe cases it can even cause defoliation of the plant. There are many fungicide products labeled for black spot on roses. Among the less toxic, natural options are: Soap-Shield (a soap spray containing copper), and Remedy (contains sodium bicarbonate or "baking soda").
Soap shield is available from:
Gardens Alive, 5100 Schenley Place, Lawrenceburg, IN 47025, (812) 537-8650
Remedy is available from:
Gardener's Supply Company, 128 Intervale Rd., Burlington, VT 05401-2850, Tel: 800-863-1700
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