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Gardening Tip!
Black Spot and Powdery Mildew:
Two of the Most Common Rose Diseases
Summer. Finally all the hard work and preparation on your perennials, bushes, and shrubs has paid off with beautiful, bountiful blooms. Everything is going well until you notice that your roses do not look quite right. You can’t put your finger on it, but something is wrong. There is a good chance that your rose could be host to a disease. Two of the most common rose diseases include black spot and powdery mildew. Black Spot
Black spot is identified by black spots on the top of leaves or stems of roses. Typically they are found surrounded by a yellow halo. Over time, if black spot is not treated, leaves will eventually turn completely yellow and fall off, weakening the rose plant. Blooming will gradually be reduced and the weakened plant may not survive the winter.
Prevention: Because black spot occurs during wet periods, it is important to plant your roses in bright sunny areas that will aid with leaf drying following rain, nightly dew, or watering. The fungus spreads through water. Additionally, a routine spray program will help deter black spot from forming in the first place. If your rose does become infected, it is important to dispose of the infected leaves by burying or burning them, especially before winter because the disease will reappear in the spring if the infected leaves are still present.
Black Spot
Unlike black spot, powdery mildew is carried by wind during hot and humid days. It is identified by a white, powdery coating on leaves, stems, and buds. New leaves often become curled and twisted. Older leaves will not look affected on the top of the leaf, but the underside will exhibit the common white, powdery residue.
Prevention: In a similar fashion to black spot, make sure that the roses are planted in a sunny, open space that allows for air movement. The faster the leaves dry, the better. Furthermore, infected and dead leaves must be disposed of in order to prevent the disease from spreading to healthy leaves. A routine spray program will aid in preventing powdery mildew from appearing on your roses.
Powdery Mildew
The good news is that you are not alone in your quest to save your roses. Many others have struggled with these diseases as well. This is great because there are many products on the market that help to treat and prevent these diseases. Delhi Flower and Garden Center is home to a plethora of different treatment and prevention options. Stop by today and talk to an expert!
Need more information or have a different plant related problem? Visit our More Articles page for links to more articles and links to other professional web sites.