Black Spot
A disease on the foliage of roses caused by moisture.
Additional Information
To avoid black spot, plant disease resistant roses. Clean up after pruning. You can use a fungicide such as captan, copper, or lime sulfur during damp weather. They are most effective when you follow the instructions carefully. You can also use baking soda (sodium bicarbonate) at a rate of one teaspoon to one gallon. Use in the morning to prevent sun scald. You can also try neem oil.
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