Analysis of the Causes of Dead Seedlings in Chinese Cymbidium and Preventive Measures

Causes and Prevention of Dead Seedlings in Chinese Cymbidium

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Orchid seedlings develop scorched tips, yellow leaves, yellow foot sheaths, rotten hearts, rotten roots, and rotten pseudobulbs, and eventually the entire plant dies, causing huge economic losses to investors in fine Chinese Cymbidium varieties. Orchid enthusiasts have different opinions, and only when growing becomes difficult do you truly understand orchids. After investigation and analysis, the main causes are: First, excessive fertilizer strength. The growing medium for Chinese Cymbidium should be lean rather than rich. When mixing it, do not worry that fertility is insufficient and add too much heavily fertilized medium. If the growing soil is found to be too rich, it should be replaced promptly or treated technically. During the management period for Chinese Cymbidium, if it can grow normally relying on the medium, there is no need for extra fertilization. When fertilization is truly needed, organic fertilizer should be the main type, and organic fertilizer must be decomposed before use. Undecomposed grass matter, bone meal, oil cake, etc. must not be used directly to fertilize orchids. Special orchid nutrient solutions are usually also a kind of fertilizer, and fertilizer damage from excessive application should be prevented. When using organic fertilizer or chemical fertilizer, it must never be too concentrated; apply dilute fertilizer frequently. Second, excessive pesticide use. Any medicine has side effects, just as a healthy person who takes medicine every day will develop problems even without illness. Commonly used medicines in Chinese Cymbidium management can be divided by purpose into sterilizing medicines, insecticides, and hormone medicines. Frequent use or excessive doses of different medicines can all cause pesticide damage. Prevention should come first, taking precautions before problems arise. Healthy, robust Chinese Cymbidium can go without medicine. Only when pests or diseases truly require it should medicine be used in appropriate amounts. When temperatures rise and humidity decreases, prevent medicines and fertilizers applied at normal amounts from naturally increasing in concentration and harming the seedlings. Third, excessively high temperatures. Chinese Cymbidium needs to grow in a suitable temperature and temperature-difference environment. The suitable temperature for Chinese Cymbidium growth is 15 to 30 degrees, and the suitable day-night temperature difference is 5-15 degrees. When the potting soil temperature is higher than 35 degrees, when the day-night temperature difference is extremely small, or when ultraviolet lamps shine for a long time, the plant vessels that transport nutrients for orchid growth are extremely prone to mechanical damage, and viruses and bacteria in the environment reproduce extremely quickly, making Chinese Cymbidium susceptible to viral and bacterial infection and resulting in dead seedlings. Fourth, excessively high humidity. The growing environment for Chinese Cymbidium should be dry rather than wet. Do not water too frequently, and do not water over the crown during hot, humid summer seasons, so as to prevent waterlogging from damaging roots and rotting hearts and causing dead seedlings. Fifth, insufficient air permeability. Both orchid pots and orchid rooms need ventilation. The growing medium should be coarse rather than fine. Orchid rooms should not be stuffy, and attention should be paid to ventilation. Do not let cooking fumes or factory exhaust enter the orchid room. Harmful gases breed viruses and bacteria and easily cause orchids to become diseased. Sixth, dividing them too singly. Chinese Cymbidium is a clumping plant and likes to grow in groups. Generally, it should not be divided too frequently or planted singly. Weak seedlings, old seedlings, or diseased seedlings that are too single have poor disease resistance. Introduce disease-free, robust new seedlings. Diseased orchid seedlings found should be disinfected promptly and managed in isolation. Only after they grow normally can they be placed in the orchid room to prevent cross-infection. Tissue-cultured seedlings and greenhouse seedlings have relatively weak ability to adapt to the natural environment, so they must be carefully cared for. Do not rush success or try to pull seedlings up to help them grow. In one sentence: Chinese Cymbidium is killed by fertilizer, killed by medicine, killed by heat, killed by waterlogging, killed by stuffiness, killed by division, and also killed by love.