A common backyard gardening problem is plant diseases, and roses are not invulnerable to them. Common rose diseases vary by area, as the fungi which cause many of them are affected by temperature and moisture. Some of the most common rose diseases are Black Spot Disease, Powdery Mildew, Rust, and Rose Mosaic. While rose diseases do not always kill rose plants, they often affect the leaves and make it more difficult for the rose to survive in the winter. Hereís how to spot the diseases in order to start taking care of any rose plant that has a disease.
Black Spot Disease
This disease, as its name implies, appears as black spots on the upper surfaces of the roseís leaves. It is caused by a fungus, which is allowed to propagate in moisture, which can come from rain or watering over the leaves instead of down at the soil. It can also be caught from other diseased plants, as the fungus can spread through fallen leaves, or even through composting of diseased leaves and stems. It causes most diseased leaves to drop off early, but survives through the winter on any leaves that manage to stay on the rose. It can also survive through the winter on the stem.
This disease is not harmful at low levels, merely causing small orange growths on the underside of leaves. At higher levels, leaves begin to be damaged, which can damage the plant since the leaves are the part of the plant that produces energy.
This disease is different from other common rose diseases, as Powdery Mildew does not need water. This growth, which resembles a white powder, occurs on the top and bottoms of leaves and on stems. In the summer, if roses are free of any fungi caused disease, Powdery Mildew can simply be hosed off of affected roses and thus, can be easy to take care of.
This viral disease does not kill plants. Many rose gardeners do not need to deal with this disease, as all it does it cause splotches, often yellow and green, to appear on leaves.
There are many other rose diseases, and which ones are the most common in each area changes depending on the weather in that area. Ask for free gardening advice from neighbors, friends, and fellow rose growers, or pick up one of the many books available on growing roses.
To avoid getting rose disease, start by buying disease free plants from the garden supply store. There are also many disease resistant variants of roses, which while still susceptible to disease, are at least less likely to become diseased.
Once a plant is diseased, there are many gardening tips available as to how to deal with these. An easy gardening tip is simply to prune away the affected areas. Be careful not to leave any diseased leaves on the ground, and donít put the diseased leaves and stems into compost, as compost does not always reach the temperature need to kill the fungi, and when the compost is used, the fungi will spread to the roses again. To help prevent reoccurrence of the disease, or an occurrence of any other disease, keep the rose beds clean. Clear away fallen leaves and pull any weeds.
These common rose diseases should not be too much of a gardening problem for any rose gardener, as, with early detection, they can easily be destroyed without the death of the entire rose bush and garden.