Edible Fungi Pest and Disease Control and Methods for Cultivating Young, Weak Orchid Seedlings
The reasons young, weak orchid seedlings arise include: dragon-root seedling plants grown from orchid seed development, or young, weak seedlings developed through regeneration of the pseudobulbs after the orchid plant has been damaged by humans or livestock or has died abnormally. Such seedlings have poor disease resistance, a very low survival rate, and are not easy to cultivate; generally, without 7 to 8 years it is very difficult for them to bloom. Therefore, when cultivating such seedlings, selection must be made purposefully. For example, regenerated seedlings of rare and precious orchid varieties, as well as unnamed seedling plants that you believe have relatively high cultivation value.
When first obtaining the seedlings, regardless of which variety they are, the residual roots and withered leaves should first be trimmed, and the soil and debris on the roots and leaves should be rinsed clean with clear water; then use 0.5% thiophanate-methyl or another fungicide to soak the entire orchid seedling for 5 to 10 minutes, sway it slightly, lift it out and hang it upside down in the shade to dry. After the root system turns slightly white and has become somewhat soft, it can be potted. For a single seedling or double seedlings, a pot with a diameter of 10 to 20 cm may be chosen; before use, soak it for 1 to 2 hours in a 5% sterilizing agent. For the growing medium, it is best to use fresh sawdust with low fat content and relatively fine particles; steam it or chemically sterilize it, filter off the yellow wastewater, spread it dry, and then plant. Sawdust has a certain heat-retaining and water-retaining capacity, which helps the root and bud differentiation and sprouting of the orchid seedlings. A chemical nutrient solution fertilizer (commercially available) may be applied year-round, which is very suitable for the initial directional cultivation of orchid seedlings.
After the seedlings are potted, the first watering should be thorough. After the water has drained completely from the pot holes, wait a little, then supplement with a mixture of 0.3% to 0.5% chemical nutrient solution and 0.2% thiophanate-methyl; applying it by fine-hole spray is best. Finally, use a sterile cotton ball to blot dry the accumulated water in the leaf axils of the orchid leaves, place it in a cool, ventilated place for 10 days of care, and spray a small amount of clear water on the orchid leaves morning and evening each day, with the goal of moistening the orchid leaves. After they survive, move them out; afterward the frequency of spraying water may be appropriately reduced, and every 10 to 15 days regularly apply a mixture of 0.3% and 0.1% nutrient solution plus thiophanate-methyl. The pot soil humidity should be maintained at 65 to 70%, and the temperature (pot soil) should always be kept above 18°C. After about 15 days, roots may burst out explosively, and within the same year strong seedlings can grow. If management is proper year after year, flower buds can form in 4 to 5 years.
After planting, observe the condition of the seedlings carefully at all times, pay attention to weather changes, and do a good job of heat prevention and freeze prevention and insulation. In winter, pay attention to temperature differences when using water, and let the seedlings receive more morning sunlight. Medicine and fertilizer should be applied frequently and lightly; if it is found that medicine or fertilizer has been applied too heavily and harmed the seedlings, flush with clear water, or promptly lift the roots and repot and rinse before planting again. A hygrometer can be inserted into the pot to observe temperature and humidity differences. After three years, the pot should be changed once; afterward, a humus mixed soil can be used for cultivation, and management can follow traditional care methods.