What to do if the hydroponic orchid has yellow leaves
This article shares some tips on how to deal with yellow leaves in hydroponic orchids and the best methods for treating yellow leaves in the aspect of green plant maintenance. The specific content is as follows:
During the cultivation of orchids, it is common to encounter the phenomenon of yellowing leaves, which can affect the appearance and even lead to the death of the orchid. There are many reasons for the yellowing of orchid leaves, which can be generally divided into pathological yellowing and physiological yellowing. When encountering yellowing leaves, one should not panic first, but identify the cause of the problem. Only by accurately identifying the cause can we solve the problem effectively; otherwise, it may not only fail to solve the problem but also exacerbate the leaf disease.
I. Physiological yellowing of orchid leaves
Physiological yellowing first appears in the old orchid plants, which is caused by the normal metabolism of the orchid. The lifespan of the old plants is over, and they should naturally die. This is manifested by the rapid yellowing and withering of the entire leaf of the old plant, with a very fast yellowing speed, usually completely withered within about a week.
When the nutrient supply is insufficient, the leaves of orchids will also turn yellow, starting from the old plants. During the orchid's shooting or flowering stage, a large amount of nutrients is needed to meet the growth or flowering of the plant. Weaker orchids may experience nutrient deficiencies, and the leaves will transfer nutrients back to the pseudobulb to support shooting and flowering. This nutrient transfer can cause the leaves of the orchid to turn yellow from the tip, which is commonly referred to as "retreating grass."
The physiological yellowing of orchid leaves is uniform in color, without patches of yellow here and there. The yellowing color ranges from light to dark, and the leaves remain stiff. The yellowing starts from the outermost leaf of the orchid and moves towards the central leaf, and it also progresses from the tip to the bottom rapidly, with these two trends occurring simultaneously.
What to do if the hydroponic orchid has yellow leaves
Remedy: Before the orchid's flowering and shooting stages, apply a light dose of fertilizer to provide adequate nutrients for the orchid. After flowering, another light dose of fertilizer should also be applied to replenish the nutrients.
II. Pathological yellowing of orchid leaves
Pathological yellowing appears as uneven yellow or brown spots on the leaves, with patches of yellow here and there, without any pattern. If it is not due to artistic patterns on the orchid leaves, there are three possible causes.
The first is illness, which is mainly caused by fungi, bacteria, and root rot. Anthracnose is a fungal disease that is contagious and appears as yellow spots on the leaves. In the early stage, the spots are regular, with the center darker than the edges, appearing yellowish-brown or blackish-brown in the center and yellow at the edges. In the later stage, the spots are irregular, with the center lighter than the edges, appearing grayish-white in the center and brownish-yellow at the edges.