Why do succulents rot and turn black?
The editor will tell you about the introduction of the flower clinic, why succulents rot and turn black, and the specific details are as follows:
Many flower enthusiasts do not know why succulents rot and turn black. Rot is the most common disease in succulent plants, usually caused by excessive watering or a too humid cultivation environment leading to fungal infection. It is a very troublesome fungal disease with strong infectivity and resistance. It has a wide range of hosts, and the pathogen can survive in the soil in the form of microsclerotia for a long time. It can be transmitted through seeds, infected soil, diseased tissues, and other means.
Succulents mostly grow in desert climates and are adapted to extremely dry growing conditions, so watering should never be excessive, and the soil should be completely dry between two waterings. Another cause of rot is the soil medium being unbreathable. It is essential to use a breathable and well-draining medium to ensure that water does not accumulate around the stems for more than a few minutes (the medium I usually use can be thoroughly wetted as soon as water is poured).
Some insects, such as mealybugs, can also cause rot, especially root mealybugs. These pests cause wounds when they suck the sap of the plant, which can lead to fungal infection. The manifestations of black rot are many, and by the time you notice, it is often too late. Always be vigilant about discolored areas on the plant, as well as soft and mushy stems and leaves.
Prevention and treatment methods for black rot disease:
1. Pay attention to the ventilation and heat dissipation of the potting soil. It's a common saying that the hot and humid potting soil not only creates conditions for the繁殖 of Fusarium oxysporum but also reduces the resistance of the root system. Especially after watering and then being exposed to direct sunlight, the roots in the soil are like boiling meat. Just like us humans, Fusarium oxysporum prefers cooked food over raw.
2. When transplanting, please use carbendazim to soak the roots. The resistance of the succulents during the adaptation period is weak. If there is Fusarium oxysporum in the soil, it is easy to get sick. Using carbendazim can treat the disease. If you notice that the succulents are not doing well at an early stage, using carbendazim to pour the roots is also very effective, the earlier the better. If you find that part of the succulent is black and rotten, the earlier you cut it out, the better. Once it's necrotic, it can't be saved. Not only will it not get better, but the necrotic part will become a culture medium for fungi, breeding a large number of fungi. PS: Before and after cutting, wash and disinfect your hands, and disinfect the knife and scissors to prevent transmission!
3. Prevent parasites. Parasites bite the succulents, causing wounds and creating opportunities for Fusarium oxysporum to invade.
4. Biological prevention. Many bacteria and fungi can拮抗 Fusarium oxysporum, such as Bacillus subtilis and Trichoderma. Those with conditions and interest in technology can study this. In agriculture, biological control has been widely used and has achieved good results.
For those that are black and rotten but not completely rotted, you can use a disinfected blade to dig out as much of the rotten part as possible, preferably even some of the non-rotten parts, as it might be difficult to tell whether they are infected or not.
The above shares a comprehensive introduction to why succulents rot and turn black, hoping to bring some knowledge about green plants to green plant enthusiasts.