1. Leaf swelling

It is generally harmful to the flower buds, young leaves and new shoots of Rhododendron. At first, there will be light yellow translucent circular spots on the front of the leaf, and then it will turn yellow. It's a little sunken. This will make the leaves begin to wither and fall early. When it is serious, it will also make leaf spots on the petiole, which will become very deformed and hypertrophic

Prevention and treatment methods: before the onset of the disease, especially when it shoots and leaves, some pesticides can be sprayed, and if it is found that the diseased leaves should be cleaned up immediately. If the disease occurs before germination, some pesticides can also be sprayed for treatment, and other pesticides should be sprayed after the disease

2. Leaf spot and brown spot

Both diseases directly affect its leaves, petioles and stems. The disease spots on the leaves are round, and then they will begin to expand gradually, showing irregular large disease spots and some wheel patterns. Then the disease spots will gradually change from reddish brown to dark brown, with grayish brown in the middle. No matter what kind of disease, it may make the whole plant completely wither and die

Prevention and control methods: from May to August, we can find some corresponding pesticides, make certain configuration, and then spray them every 10 days or so. A total of 7 to 8 times before and after spraying is enough, so that the development of the disease can be well controlled. In order to prevent some leaves from turning yellow, other solvents can be added

3. Coin disease

It sounds like a really strange disease. Generally, as long as it is on the injured twigs and leaves, it will be immediately covered with dense white or pink diseases, most of which are caused by aphids

Control method: first, remove the diseased leaves, and then spray some chemicals on them. In addition, master some spraying skills, so that it is not easy to have new diseases