Why do orchid leaves turn yellow? Causes and solutions for orchid yellow leaves.

Why do orchid leaves turn yellow?Compared to the knowledge of most people about why orchid leaves turn yellow, as well as the causes and solutions for yellowing leaves, the specific content is as follows:Leaf yellowing in orchids is an unavoidable issue in the process of cultivating them. Some are caused by physiological phenomena, while others are caused by diseases and pests. Therefore, we need to analyze specific problems, identify the causes, and respond calmly.The reasons for leaf yellowing in orchids can be divided into three types: art appearance, degeneration, and diseases and pests. Art appearance and degeneration are physiological phenomena that cause leaf yellowing in orchids, and they represent two different directions in the growth process of orchids. Therefore, they need to be discussed separately. This article will focus on these three aspects to provide a detailed introduction, allowing orchid enthusiasts to have a more comprehensive and in-depth understanding of yellowing leaves.1. Leaf yellowing caused by art appearanceArt appearance refers to the occurrence of colored lines or spots and patches on the leaves of orchids. This genetic change phenomenon is known as "art appearance" in the industry. It is considered an "evolution" in the normal growth process of orchids. Leaves with yellow lines are called "striped grass" or "silk grass," while those with yellow spots and patches are called "spotted grass." These orchids with art appearance are collectively known as "leaf art orchids" or "line art orchids." The yellowing of orchid leaves can be divided into five common colors: yellow, white, vermillion, red, and black.The timing of art appearance in orchids can vary, and this phenomenon is divided into three types based on the timing of leaf art appearance: early art, early bright and late dark art, and late art. Simply put, leaves that are yellow when they first emerge from the soil are called "early art"; leaves that start yellow and gradually turn green are called "early bright and late dark art"; leaves that start green and gradually turn yellow are called "late art."Why do orchid leaves turn yellow?How to determine if it's a normal art appearance?When orchid leaves show yellow lines or spots and patches, the leaves remain vigorous and glossy, do not wilt, and the yellow areas are very bright, with strong contrast to the green areas. Most have very distinct boundaries, with clear distinctions between white and yellow. If there are dark brown areas mixed in, without luster, and the leaves show signs of wilting and yellowing, lacking vitality, it is not art appearance and should be considered degeneration or leaf yellowing caused by diseases and pests. If it's art appearance causing leaf yellowing in orchids, we don't need to worry and no treatment is required. Just continue with normal cultivation.2. Leaf yellowing caused by degenerationOrchids are perennial herbaceous plants with a normal lifespan of 3-5 years. Well-cultivated orchids can live up to 5 years or more. After reaching their lifespan, the orchid leaves quickly turn yellow and die. Leaf yellowing at the end of the normal lifespan is considered normal degeneration in orchids.Normal degeneration in orchids starts from the bottommost, outermost leaves, moving inward and downward, with the entire leaf quickly turning yellow. The longer it takes, the darker the color, eventually turning into yellowish-brown, brown, and finally withering. There is nothing we can do about this situation; we just need to cut off the withered leaves when they do.