Ecological Environment Requirements for Crop Growth

(1) Temperature:Cold OrchidThe vast majority are distributed in the shade of broadleaf trees in subtropical and temperate regions. Because its cell walls are thin and its cuticle is also thin,Cold Orchidprefers a warm climate, fearing both heat and cold, and is especially afraid of a sharp drop in temperature after the Autumn Equinox, followed by successive dry northwest winds, which cause large-scale leaf drop and seedling death.Cold OrchidDuring the growing season, the temperature is generally 18-28°C. When summer temperatures exceed 30°C, or when the average daily temperature in winter falls below 10, growth slows or the plant enters a dormant stage. When the temperature reaches 35°C, the orchid plant will show abnormal conditions such as scorched and curled leaves. After the Autumn Equinox, a windbreak wall should be set up on the northwest side of the orchid shed. (2) Light: Cold Orchid mostly grows in well-shaded environments and is a typical shade-loving group among Chinese orchids, but different types of Cold Orchid have different requirements for light duration and intensity. Winter-flowering Cold Orchid enters the flower bud differentiation stage during the period of strong sunlight and high temperatures in late summer and early autumn. Then, in early winter, when sunshine gradually shortens and temperatures tend to drop, it enters the flowering stage. Spring and autumnfloweringCold Orchid is a neutral type between long-day and short-day Cold Orchid, with higher physiological adaptability to changing environments, which may be closely related to the living habits of its hybrid parents. For example, when Cold Orchid is crossed withSpring Orchidits offspring's growth habit tends towardSpring Orchidand its growing environment requirements are likeSpring Orchidthe same ecological environment. When Cold Orchid is crossed with Autumn Orchid, its offspring's growing environment requirements are the same as those of Autumn Orchid. An orchid nursery for cultivating Cold Orchid should imitate the natural ecological environment of its native habitat, so that Cold Orchid grows in a cool, shaded environment with scattered sunlight. In rural areas, using locally available materials and plant shading is relatively ideal. At present, shade nets with different shading densities are generally used to regulate light. In summer and early autumn, Cold Orchid requires a shading rate of 80%-90%, and especially those with good leaf artistry require an even higher shading rate. In rural areas, bamboo curtains, reed curtains, straw curtains, etc. that are easy to move can also be used, and should be selected according to the convenience of materials. (3) Water: Because Cold Orchid has thin cell walls and a thin cuticle, it is prone to internal water imbalance, so it requires a growing environment with heavy mist and good drainage in broadleaf forests and mixed forests. Cold Orchid likes moisture but fears excessive water retention. For home cultivation of Cold Orchid, rainwater, river water, and well water are generally used for irrigation. In cities and towns,orchid growingmostly uses tap water. However, it must be stored for several days before use. The frequency of watering depends on the season and the substrate: when coarse hard material is used as the growing medium, water frequently in summer and autumn; in winter, water must be controlled; in other seasons, keep the growing medium moist. When young shoots grow to 1.5-2 cm, this is exactly when new roots are growing; at this time watering must be done with care, otherwise it will cause root rot and bud death. As for watering time, except when it is scorching at noon and cold at night, watering can be done at other times during the day, but it is best to do it at sunrise in the morning. In short, it is necessary to maintain an ecological environment in which the roots of Cold Orchid remain moist but not wet, dry but not parched, and the air humidity is high. (4) Humidity: The reasonable regulation and balance of humidity, temperature, and light are necessary for photosynthesis. And judging from the cell structure of Cold Orchid leaves, it needs the moisture of relatively high air humidity to display its towering plant shape and elegant posture. Cold Orchid grows in misty mountain areas at medium altitude, where the ecological environment has relatively high humidity. Therefore, whencultivatingCold Orchid, the humidity inside the shed in spring should be kept at 50%-60%; in summer and autumn, the humidity should be kept at 80%-90%; during the winter dormant period, the humidity can drop to 30%-40%, and at night it should be even lower. In short, the humidity requirements of Cold Orchid are: high during the growing season, low during the dormant season; high during the day, low at night; high at high temperatures, low at low temperatures; high on clear days, low on cloudy days. (5) Ventilation: In its natural environment, Cold Orchid is ventilated on all sides, and the air around its rhizosphere also circulates. Especially for Cold Orchid growing on slopes under tree shade, it basically grows upward in one direction, and part of the root system is even exposed on the surface soil. Ventilation provides Cold Orchid with fresh air, from which it absorbs carbon dioxide and other free components, all of which are necessary for the metabolism of Cold Orchid. At the same time, ventilation can also remove polluted harmful gases from the space, regulate and lower room temperature, and inhibit the breeding and spread of pathogens. Ventilation has two aspects: first, maintaining ventilation of the Cold Orchid itself, including ventilation of the rhizosphere substrate and ventilation between Cold Orchid plants; second, it refers tocultivationventilation inside the Cold Orchid shed, especially in the stuffy hot summer, when ventilation is even more important. (6) Fertilizer: In addition to organic fertilizer and inorganic fertilizer, Cold Orchid also needs certain trace elements to obtain a full supply of nutrients. When applying fertilizer, be careful and cautious to avoid damaging the roots and causing seedling death. When using organic fertilizer, it must be fermented for several months, then the extract liquid should be diluted 8-10 times with water for watering or mixed into the substrate. When applying chemical fertilizer, different chemical elements should be used according to the different growth stages of Cold Orchid, and after dilution according to the instructions, it should be sprayed. The fertilizing season generally starts in mid-spring and ends in early winter. In spring and winter, nitrogen-phosphorus-potassium compound fertilizer is generally applied once each by spot application or dissolved in water, with the concentration and amount depending on the condition of the seedlings. At ordinary times, "Lan Jun Wang" produced in Sichuan, potassium dihydrogen phosphate, and trace elements are used for foliar spraying. The application concentration should follow the label. The time for fertilizing should be chosen on a sunny day with suitable temperature, avoiding strong sunlight and excessively high temperatures at noon that harmorchids. If the temperature is too low, it is not easy to absorb and the fertilizer is wasted. (7) Preventing air pollution: Cold Orchid needs fresh, clean air. If the air is polluted, it will cause poor growth, corrosion of the leaf surface, discoloration, and even necrosis, as well as early withering of flowers, yellowing and wilting of sepals, and in severe cases death of the whole plant. For home cultivation oforchids, they are often contaminated by smoke (oil) fumes and dust, causing the leaves to become "white-haired", and even the leaf tips to scorch and die. First of all, prevent smoke (oil fumes) from invading the orchid shed, often ventilate (exhaust) the air inside the shed, and spray and washorchids. Especially after the Beginning of Spring, it is even more necessary to clean the orchid plant leaves. Keeping the leaf surface clean and smooth is beneficial to photosynthesis and enhances the accumulation of organic matter. Ensure the supply of nutrients needed for the germination and growth of orchid buds. (Yang Jixin, Wuyishan City Orchid Association, Fujian)