The occurrence of coal pollution disease has a very important harm to the leaves of Hibiscus. It will make the leaves and flower branches of Hibiscus gradually turn yellow and wither. There will be a lot of black powder layers around the leaves of plants in the disease period, which seriously affect the beauty and ornamental of the whole hibiscus.
Prune the hibiscus properly, keep the hibiscus ventilated and transparent, reduce the humidity of the surrounding environment, and spray the sulfur mixture during the dormancy period of the plant to eliminate the disease source for prevention and control. Aphids are one of the major factors that cause coal pollution. Spraying 40% Omethoate can reduce aphid excretion and prevent coal pollution.
As the same as the coal pollution, hibiscus leaf spot damages the leaves of plants, making the spot appear Korean brown, polygonal, 3-10 mm in size. When the surrounding humidity is heavy and the humidity is too high, many dark brown fluffy substances will be produced on the back of the leaves. Diffuse mass, high incidence.
In the early stage of the disease, 50% carbendazim 500 times solution should be found and sprayed in time for prevention and control, about once a week to twice a week, and 2-3 times continuously.
Leaf spot disease also mainly occurs in the leaves of Hibiscus. In the early stage of its onset, the leaves of plants gradually turn yellow and slowly begin to wither. This disease will directly affect the beauty of Hibiscus.
The application of 65% zineb powder has a good control effect on this kind of disease. When the leaf spot occurs, it needs to be sprayed thoroughly.
