How to prevent and treat rot disease in orchids? A must-read for orchid growers

For orchids, the harm caused by rot disease is extremely serious, and it spreads rapidly. Orchid rot disease mainly includes two types: soft rot and black rot.

In the early stages of soft rot, tiny brown water-soaked spots appear on the leaves, then expand into black damp patches. At this point the lesions are extremely prone to breaking open and exuding a foul-smelling liquid. After that, the orchid plant will quickly rot. This disease generally occurs easily in rainy and humid seasons above 30°C.

Black rot, on the other hand, is a fungal disease that mostly occurs on the leaves, root base and growing point. At the affected area, semi-transparent spots first appear, and the spots gradually expand, the tissue turns black, and it gradually rots. When it begins to appear on the root system or underground stem, attention should be paid. If no prevention and treatment are carried out, it will soon spread from the root system to the entire underground stem, until the plant is completely destroyed. In a very short time, this disease can turn the orchid's rhizome black, and the leaves blacken and rot.

Prevention and treatment methods: After an orchid is infected with rot disease, repot it and change the soil in time, cut off all tissues at the diseased parts and burn them in a centralized manner, then wash and disinfect the cut surfaces with clean water, apply sulfur powder, and place it in a cool, ventilated place to dry. After the cut surfaces shrink and dry, repot it again. After repotting, do not water or spray water for 3 to 4 days, and spray once with a solution made from 50% thiram plus 500 times water. The growing environment should be given enhanced ventilation and light. Diseased plants that have been rescued should be temporarily isolated from other orchids to avoid infection. Only after they grow normally and are no longer contagious may they be placed together with other orchids.