| The leaves on my rose bushes have started getting spots on them and the leaves turn yellow and fall off. I don't know what to do. I have sprayed the leaves with a soapy solution of dish liquid (Dawn) and water. But this didn't help. |
| Based on your description it sounds like your rose has "black spot." A fungus causes black spot on roses. Some cultural practices may be helpful in controlling it. These include planting varieties resistant to it, ensuring your plants are in a location with good air circulation, avoiding wetting the leaves when watering, and cleaning up, removing and destroying any infected leaves. Do this especially well each fall to minimize reinfection from year to year. Each winter, you might even try handpicking off any remaining leaves from the bushes. A clean layer of organic mulch (such as shredded bark or half finished compost or chopped leaves) applied before the plants leaf out again in spring should also help prevent reinfection. It prevents the fungus from splashing back up onto the plants. Neem oil may also be helpful. Neem controls aphids and mites on your roses, and the oil version of neem also will control powdery mildew and black spot. Some gardeners have had success using baking soda and water sprays to control black spot. Tests in England indicated that 1.5 tablespoons of baking soda in 1 quart of water was effective. Add just a a few drops of dish detergent to help it stick. You may want to try it and see for yourself. Caution: Always test something new like this on a few leaves and wait a few days to see the results before spraying all of your plants. |
