How to grow orchids? A detailed explanation of orchid ecological habits and cultivation management techniques

1 Orchid cultivation

1.1 Ecological habits of orchids

Orchids prefer a warm and humid environment, and conditions that are warm in winter and cool in summer are especially suitable. When growing orchids, it is essential to avoid high temperatures and dryness. The growing site for orchids requires deep upper soil rich in humus, with fertile dark brown soil being the best, and it must have good permeability and water retention.

1.2 Classification of orchids

There are many varieties of orchids, about a thousand or more, and common types include Cymbidium kanran (cold orchid), Cymbidium faberi (Huilan), Cymbidium bicolor (hard-leaved orchid), Cymbidium sinense (Molian), Dongfeng orchid, Cymbidium floribundum (Tai orchid), and so on. To cultivate orchids scientifically, it is necessary to distinguish the types of orchids and understand them accordingly. This article mainly discusses the cultivation techniques for the hard-leaved orchid, Molian, and Dongfeng orchid varieties.

1.3 Selection of orchid pots

Choosing a suitable orchid pot is very important for the growth of orchids. Glazed pots are finely made and very attractive, suit the character of orchids, and can be one option, but their drawback is insufficient breathability; plastic pots have the advantages of being cheap and lightweight, but their breathability is poor; clay pots have very good aeration and should be a very good choice of orchid pot for orchid growth. Overall, what kind of orchid pot to choose mainly depends on the actual situation.

1.4 Preparation of soil

Soil is the foundation for orchid growth. Scientifically prepared soil can allow orchids to grow healthily. Soil with good breathability and drainage, with a pH of 5.5 to 6.5, is most suitable for orchid growth. Orchid growing medium can be composed of one or more of the following substrates: ① Leaf mold substrate: this kind of soil can be prepared artificially. The main preparation method is to pile fallen leaves together, add fertilizer, mud, water, and other components, and after the processes of sealing, decomposition, and sieving, leaf mold is obtained; ② Bamboo root soil substrate: obtained from the root area of bamboo clumps that have grown for many years. This kind of soil contains bamboo rhizomes, bamboo roots, and rotted bamboo leaves, is rich in nutrients, and is relatively loose; ③ Mountain soil substrate: generally obtained from mountain forests. Mountain forest soil contains the fallen leaves of various plants, is loose, and has good breathability. After choosing the growing medium, it must be sterilized and disinfected before use, and the soil pH adjusted to a range of 5.6 to 6.5.

1.5 Preparation of orchid seedlings

The most suitable preparation period for orchids is around Yushui. After the purchased orchids are pruned and disinfected, they can be cultivated. Repotting work should be combined with division propagation and pot changing and other steps. Generally, when taking out the orchids, ensure the soil has a suitable temperature of 20 to 28°C, and try to ensure the leaves do not get wet. After taking them out of the ground, prune the rotted roots, broken roots, and dried leaves. Place the trimmed orchid roots in a 50% thiophanate-methyl 1000-fold disinfectant solution for 10 to 15 min, then take them out and place them in a ventilated area to dry.

1.6 Cultivation of orchid seedlings

Cultivating or repotting orchids requires choosing a suitable season. Generally, the Qingming period is the best time for cultivating and repotting orchids. The specific cultivation methods are as follows:

① Select a flower pot of appropriate size, cover the drainage hole at the bottom of the pot with a tile piece, then use relatively loose material such as ash and slag to fill the flower pot, filling it to a range between 1/3 and 1/2 of the pot, and cover the top with nutrient soil;

② During transplanting, try to avoid the orchid roots coming into contact with the inner wall of the container, and ensure the root fibers are in a naturally spread state; ③ Hold the orchid leaves with your hand, slowly fill soil around the orchid roots, and gently lift the orchid upward to ensure the roots spread naturally, while also adjusting the position and height of the orchid plant until the plant is slightly above the pot surface;

④ For a well-planted orchid, spread small stones or sphagnum moss, etc., on the soil surface, which is both attractive and helps regulate moisture;

⑤ After the orchid is planted, the first watering should be thorough. When using a spray bottle to spray the leaf surface, be careful to apply force evenly, with small water droplets being best. Afterward, place the orchid in a water basin to soak, and a spray bottle may be used to moisten the leaf surface.

2 Orchid management

2.1 Environment and planting site

Orchids prefer cool shade, and 10 to 25°C is the most suitable temperature for orchid growth. Temperatures that are too high or too low will seriously hinder orchid growth. To avoid this situation, common methods include building shade sheds and sprinkling water. The most suitable air humidity for orchid growth is 60% to 80%. Humidity in a greenhouse generally does not meet the requirements, and methods such as sprinkling water and appropriate shading can be used to increase humidity. The orchid growing environment should be kept as far away as possible from industrial areas such as chemical plants. It is best to face the southwest direction and also have a sheltered location to avoid damage from strong light.

2.2 Water management

Spring water or purified water is the most suitable water source for orchid growth. In cities, spring water and purified water are hard to find, so tap water can be left to stand for 2 to 3 d to remove chlorine before use. Watering should also depend on the specific growth condition of the orchids and the weather conditions, and should not be too frequent. In particular, watering in spring should prevent excessive wetness, while summer temperatures are higher, so sufficient moisture must be ensured. Autumn is most suitable when neither dry nor wet, and in winter watering should be minimized as much as possible, preferably on sunny days.

2.3 Fertilizer management

Orchids like fertile soil. If the quality of the base fertilizer is not good enough, topdressing is necessary. Base fertilizer and topdressing are distinguished by fixed timings. Generally, the leaf mold and pig manure, etc., added during cultivation are base fertilizer, while topdressing is applied when orchid growth is limited because the quality of the base fertilizer is insufficient, so additional fertilizer is applied. The specific fertilization time should depend on the orchid variety and climate. Because water evaporates slowly on cloudy days, it is not suitable to fertilize. At temperatures above 30°C, water evaporates too quickly, so it is also not suitable to fertilize. Therefore, the best season for fertilizing is spring and summer, the most unsuitable season for fertilizing is winter, and a small amount of fertilizer can be applied in autumn. There are the following two fertilization methods: ① mix fertilizer with base fertilizer; ② fill water-soluble fertilizer into a container and apply it to the flower roots by spraying, being careful not to let the leaf surface get fertilizer on it.

2.4 Prevention and control of pests and diseases

Compared with most ornamental plants, orchids have relatively fewer pests and diseases. The main orchid diseases are brown spot disease and anthracnose. The main causes are overly wet potting soil and long-term lack of sunlight. To prevent orchid pests and diseases, the following aspects of work need to be done well: ① when planting, choose disease-resistant varieties as much as possible; ② when maintaining indoors, ensure a pot spacing of 10 to 15 cm; ③ water appropriately, promptly cut off diseased leaves, and appropriately spray 40% sterilizing agent 800-fold solution; ④ once orchids develop disease, increase ventilation, supplemented by spraying 50% carbendazim 800 to 1000-fold solution.

2.5 Protection of flowers and leaves

Orchid leaves should also be protected in daily care. If contamination is found, it should be addressed promptly, and withered, yellow, or diseased orchid leaves should be cut off promptly. In addition, each orchid seedling does not need to retain too many flower buds; keeping one is enough. There are many flower buds in the early stage after emerging from the soil, so pruning should be carried out, and retaining one high-quality flower bud is sufficient. To prevent orchids from being pollinated and setting seed, the flowers must be cut off before they wither. If the purpose of cultivation is hybrid breeding, orchids should be artificially pollinated.