What to Do About Aloe Vera Black Spots
As a star variety of indoor green plants, aloe vera leaves with mysterious black spots often leave growers at a loss. These seemingly ordinary spots are actually signals of distress from the plant, and if not handled properly, they can lead to the entire plant withering. This article will delve into the mechanisms behind the formation of black spots and provide professional-level prevention and treatment solutions.
Analysis of the Three Main Causes of Aloe Vera Black Spots
Pathological Characteristics of Fungal Infection
(T-J) bacteria are the main source of disease, spreading through the air and irrigation water. Initially, pinpoint-sized water-stained spots form on the back of the leaves, which expand to 3-5mm diameter concentric ring patterns within 7-10 days, with the edges showing a deep brown raised band, and the central tissue gradually drying and sinking.
Environmental Factors Inducing Mechanism
When the air humidity is >75% and the temperature is between 22-28°C, the germination efficiency of spores increases by 300%. Especially during the plum rain season, if the potted soil is not drained in time and the water content exceeds 40%, the root respiration is obstructed, leading to a decrease in disease resistance.
Pathway of Infection from Physical Damage
Small wounds caused by transplanting increase the risk of infection by 65%, and the risk of cross-infection increases by 80% when pruning tools are not sterilized. It is recommended to use a flame-sterilized scissor and apply charcoal powder to the cut surface to form a protective layer.
Five-Step Professional Treatment Plan
Isolation of Lesions
Remove the diseased leaves immediately with sterile forceps, place them in a sealed bag for high-temperature inactivation. Wipe the operation surface with 75% alcohol before and after the treatment to avoid spore dispersal. Spray healthy leaves with a 0.1% baking soda solution to establish a protective barrier.
Accurate Application of Pesticides
Alternately use 25% Prochloraz emulsion (diluted 1500 times) and 80% Mancozeb (diluted 800 times), focusing on the back of the leaves. It is recommended to apply the pesticide from 18-20 pm, and combining with 0.1% silicone surfactant can increase the adhesion rate of the solution by 40%.
Environmental Control Measures
Install a circulating fan to maintain air circulation, allowing the leaf surface moisture to evaporate within 2 hours. Use bottom watering methods, combined with a ceramic stone drainage layer, to keep the substrate humidity stable at 30-35%. Use far-infrared heating pads in winter to maintain a root zone temperature >15°C.
Long-Term Preventive Management System
Apply seaweed micronutrient fertilizer monthly to enhance cell wall thickness, making it 50% harder for pathogens to penetrate. Use Bacillus subtilis every quarter for biological control, establishing a probiotic protection network. Rotate the pot orientation regularly to ensure uniform light exposure and enhance the plant's immunity.
Systematic prevention and treatment can shorten the recovery period of aloe vera to 28-35 days, with the survival rate increasing to 92%. It is recommended to establish a maintenance log, recording temperature and humidity changes and the time of pesticide application, to form a personalized prevention and treatment plan. When new leaves fully unfold and no new spots appear, it indicates the success of the treatment plan.