Detailed Explanation of Coral Tree Planting Methods and Technical Points
Coral tree, also known as cockspur coral tree (Erythrina crista-galli), is native to tropical America. It prefers a hot, humid environment with ample light, is not cold-tolerant, tolerates slight shade, and grows best in well-drained, fertile sandy loam. Coral tree requires very careful maintenance; its root system is relatively sensitive to moisture, temperature, oxygen and fertilizer concentration.
Propagation: mainly by cuttings, best done in April to May. Cut sturdy, well-developed branches 15-20 cm long and insert them into a sand bed, keeping the environment shaded and moist; roots form 15-20 days after insertion.
Pruning of coral tree
For potted coral tree care, repot every spring and carry out pruning and shaping at the same time, removing dead branches and cutting back long branches to encourage the formation of more flowering branches.
Watering coral tree
In summer, water once each morning and evening; as temperatures drop and evaporation decreases, the frequency of watering should be reduced accordingly. Generally, water only after the potting soil has dried. Watering should normally be done before noon; watering after noon will lower the soil temperature, which is unfavorable for plant growth. Each watering should soak through. The amount of water should be such that a little drains from the drainage hole at the bottom of the pot.
Fertilizing coral tree
Attention must be paid to fertilizing coral tree; it likes fertilizer and mainly needs more nitrogen fertilizer during the growing period. Insufficient nitrogen fertilizer will cause the lower leaves to drop. In addition to applying slow-release base fertilizer when potting (rotted oil cake, chicken manure, bone meal, etc.), topdressing should begin 7-10 days after pinching. Topdressing should be light rather than concentrated, and concentrated fertilizer should be avoided; apply once a week. For topdressing, fully rotted cake fertilizer water or soaked hoof and horn shavings water can be used. As flowering approaches, phosphorus components should be increased, such as aqueous solutions of superphosphate, ammonium phosphate nitrate, etc. This can make the bract leaves brightly colored.
During the growing period, coral tree should be fertilized once every half month, and 1-2 additional applications of phosphorus-potassium fertilizer should be given during the flowering period; in midsummer, keep the potting soil moist.
Coral tree grows very vigorously. Under reasonable water and fertilizer management, sufficient light and good ventilation, the plant grows robustly and often tends to be too tall; although the branches are thick and the leaves are substantial, the imbalance in size and height when grown in a flowerpot detracts from its ornamental value. Therefore, chemical treatment can be adopted for artificial control. Generally, spraying 0.5% daminozide (B9) or 1,500-3,000 ppm chlormequat (CCC) on the leaf surface or pouring it into the potting soil can shorten the internodes of coral tree branches and dwarf the plant.
Pests and diseases: Fusarium wilt, anthracnose and root rot often occur; Bordeaux mixture can be sprayed on the leaves 2-3 times, or 50% thiophanate wettable powder at 1000 times dilution can be sprayed. Among insect pests, root-knot nematodes can be controlled by drenching with diluted 80% dichloropropane emulsifiable concentrate.
Uses: The coral tree has sparse, graceful leaves and blooms in early summer; its deep red raceme resembles a string of red crescent moons, brilliant and eye-catching. It is suitable for planting in parks and courtyards, and if potted it can be used to accent indoor environments.