How to grow a Radermachera sinica? Detailed guide to growing a Radermachera sinica
Radermachera sinica is an ornamental plant often seen in many home and office environments, but many people do not know how to grow it. Radermachera sinica likes a hot, humid environment with plenty of sunlight. It tolerates high temperatures, fears cold, prefers moisture, and dislikes dryness. It grows in valley or flatland open forests. For cultivation, use loose, fertile, well-drained loam and sandy loam rich in organic matter.
Propagation techniques for Radermachera sinica
1. Sowing: Around the end of December, when the capsules are close to splitting and the seeds are fully mature, harvest the long strip-shaped capsules, dry them, and release the winged seeds; after rubbing them, winnow away the membranous winged seed fragments, and store them dry until sowing the following spring. They can also be soaked for 2 to 3 hours, then mixed with moist sand, spread thinly in a large plastic basin inside a shed, keeping the seeds and sand moist, and checked frequently to prevent mold; after the seeds germinate, sow them in the ground. For dry-stored seeds, between March and April, first soak them for 3 to 4 hours, remove them and spread them out briefly to dry, then mix them with sandy soil and broadcast them on a prepared seedbed, cover lightly with a thin layer of soil, cover with plastic film to retain moisture, and after the seeds emerge remove the film and set up a light shade frame for shading. For sale.
2. Cuttings: Between March and April, when the ambient temperature reaches about 15°C, cut 1- to 2-year-old woody branches, about 15 cm to 20 cm long, remove all leaves, with the lower cut preferably located 0.5 cm below a node, and insert them into a sandy loam seedbed, with the cutting inserted to a depth of about 1/3 to 1/2 of the cutting length. During the period when the lower cut heals and roots form, spray water to keep the seedbed moist. Only after a well-developed root system has grown can they be transplanted into pots with a soil ball; preferably 2 to 3 plants should be planted together, so they can take shape early for sale.
3. Layering. Between March and April, on 2-year-old vigorous branches or stems below a node, carry out ring-barking, with the width of the bark removed generally 2 to 3 times the diameter of the layered stem. Below the ring-barked wound, tie a piece of 15 cm × 20 cm plastic film. [water opening], and tie it against a thick main trunk to prevent it from drooping and being broken by wind. By late autumn, after the ring-barked wound has grown a relatively well-developed root system, cut it away from the mother plant and plant it separately in a pot.
How to grow a Radermachera sinica
1. Temperature: Radermachera sinica likes a warm, hot environment, and the suitable growing temperature is 20°C to 30°C. During the intense heat of midsummer, when the ambient temperature reaches above 30°C, shade should be provided appropriately by building a frame, and spraying water on the environment and leaf surfaces should be increased, or it can be moved to a ventilated, cool place with light shade to spend the summer. As late autumn arrives, when the ambient temperature drops to about 10°C, it should be moved into a shed in time. During overwintering, it is best to maintain a shed temperature of no lower than 8°C, and at minimum no lower than 5°C, so as to avoid cold damage to the leaves or leaf drop. For household potted plants, they can be moved into a room with air conditioning or an electric heater to ensure the room temperature is no lower than 8°C, so they can pass the winter safely. Note: In winter, the shed temperature for growing Radermachera sinica should be kept no lower than 8°C, otherwise cold damage may easily occur, and even the whole plant may die.
2. Light: Radermachera sinica is a light-loving plant, and can also tolerate slight shade; full sun and semi-shade environments are both acceptable. Its seedlings are relatively shade-tolerant, and in summer a frame should be set up for shading. Potted plants should be placed in front of a window with ample light or indoors during indoor display. If placed in a dim indoor area for a long time, leaf drop is likely to occur. For household potted plants, during overwintering they can be placed in front of a window or in a higher position in front of a balcony, so they can receive as much light as possible.
3. Water: Growing Radermachera sinica requires a relatively moist soil and display environment. During the seedling stage, the seedbed should be kept moist, and in the hot, dry season after summer begins, even more attention should be paid to water supply. For potted Radermachera sinica, in order to keep it from growing too tall, watering can be appropriately controlled when new shoots sprout in spring, and it is enough to keep the potting soil relatively moist. For potted plants displayed indoors, in addition to keeping the potting soil moist, the plant should also be sprayed with water 2 to 3 times a day during hot seasons. For plants placed outdoors for maintenance in summer and autumn, spraying of the plant and the surrounding micro-environment must be strengthened to create a cool, moist, suitable environment for them. For plants placed indoors in winter, because the general indoor temperature is below 10°C, the plant enters a dormant state, so do not water too much, to avoid waterlogging and root rot; every 2 to 3 days around noon on clear days, spray the plant once with slightly warm clean water, to maintain its fresh appearance and also increase environmental humidity. In addition, Radermachera sinica can also be grown hydroponically.
4. Soil: For potted Radermachera sinica, use a culture soil that is loose, fertile, well-drained and aerated, and rich in organic matter. It is usually mixed with 5 parts garden soil, 3 parts leaf mold, 1 part decomposed organic fertilizer, and 1 part river sand. During the growing season, loosen the soil once a month to ensure the root area is always in a well-aerated state. In the plum rain season, for potted plants placed in open-air environments, check the potting soil promptly after each heavy rainfall; if water accumulation is found in the pot, drain it as soon as possible, and after the potting soil dries, repot and change the soil. Under normal circumstances, for small and medium household potted plants, repot once a year in early April when they are brought out, to meet their soil fertility requirements for a full year of growth.
5. Fertilizer: For potted Radermachera sinica, in addition to adding an appropriate amount of decomposed cake fertilizer and 3% multi-element compound fertilizer to the culture soil, topdressing should also be given continuously. During the growing season, apply a quick-acting liquid fertilizer once a month, usually decomposed cake fertilizer water. For a small number of household potted plants, or for large potted plants displayed in public places for a long time, a small amount of multi-element slow-release compound fertilizer granules can be buried regularly, or a mixed solution of 0.2% urea plus 0.1% potassium dihydrogen phosphate can be applied. For potted plants in northern regions, after the Mid-Autumn Festival, apply 0.3% potassium dihydrogen phosphate solution 2 to 3 times consecutively, to increase the plant's cold resistance and help it overwinter safely. When the summer temperature is above 32°C, and after the temperature is below 12°C in late autumn and early winter, topdressing should be stopped.