What Causes Black Spots on Epipremnum aureum?
As a common ornamental leaf plant in offices and homes, Epipremnum aureum is loved for its tenacious vitality. However, irregular black spots on the leaves often reveal critical issues in the maintenance process. This article systematically analyzes the four major pathogenic factors to provide a scientific solution for plant enthusiasts.
I. Black Spot Issues Caused by Environmental Factors
Sharp Temperature Fluctuations
Epipremnum aureum is highly sensitive to temperature changes. When the nighttime temperature drops below 15°C, the cellular tissue will react to the low temperature with frostbite. Especially in the winter, the temperature of the glass surface at the windowsill may be 3-5°C lower than that indoors, creating a localized low-temperature zone.
Imbalanced Light Intensity
While Epipremnum aureum is shade-tolerant, complete darkness can lead to insufficient photosynthesis. It is recommended to use the "diffused light supplementation method": receive 2 hours of soft light before 10 am each day and use a 40% light transmission shade net to filter the intense midday sunlight.
II. Preventive Strategies for Pathogenic Black Spots
Building an Air Circulation System
A closed environment can easily trigger fungal diseases such as gray mold. The "intermittent ventilation method" can be used: open the window for ventilation 3 times a day, each for 20 minutes, combined with a circulating fan to create air movement. Maintaining 55%-65% air humidity can effectively inhibit the reproduction of pathogens.
Comprehensive Control of Leaf Spot Disease
After diagnosing leaf spot disease, the "three-step treatment method" should be implemented immediately: ①消毒剪刀修剪病叶 with alcohol-disinfected scissors to prune the diseased leaves ② spray 50% mancozeb 800 times liquid ③ isolate the diseased plants for 2 weeks of observation. Regularly wiping the leaves with bamboo vinegar solution can enhance disease resistance.
By establishing a maintenance system that integrates temperature warning, light control, and ventilation humidity, combined with early intervention for diseases, it is possible to effectively prevent more than 95% of black spot issues. It is recommended to conduct leaf microscopic examinations monthly and promptly remove the latent pathogen spores on the back of the leaves.