Black spot is a rose fungus that attacks only roses. The black spots found on the leaves are fungus itself, not dead spots. It lives on the canes and on fallen dead leaves during the Winter and then spreads to the leaves of the living roses when the weather is wet or moist. When roses are grown in areas in which Summers are warm and humid, are most likely to suffer black spot.
Use apple cider vinegar to use it as a spray to combat many fungal diseases, including black spot on roses. Make the spray by mixing 3 tablespoons apple cider vinegar with 1 gallon water. Spray in the morning so that the plant has time to dry out before evening. Repeat as necessary.
Ugly black spots on the rose leaves, sometimes yellowish edges on the leaves are signs of black spot.
Raking up dead leaves around roses that are already planted helps stop the spread of black spot to other roses. When you first notice black spot starting on your plant, apply a baking soda spray. Destroy all affected leaves. Good air circulation around your plants will inhibit black spot on the leaves. It is important to water your roses early in the day and never work on roses when they are wet.
The first potatoes were cultivated in Peru about 7,000 years ago.