How to grow oleander bonsai? Cultivation methods and precautions
Oleander is also called false bamboo-peach, because its leaves resemble bamboo and its flowers resemble peach blossoms, yet it is neither bamboo nor peach, hence the name; some also call it “willow-leaf peach”. It likes light, prefers warmth and tolerates drought. Planted in the open air, it grows well with hardly any management. Once established, it takes on the role of an “environmental guard” for its surroundings, contributing its strength to fresh air and beautiful scenery for people. Because it is toxic, please do not plant it in front of or behind houses or in places where people often walk, and set up a notice board beside it to remind everyone to “admire it only from afar, never handle it disrespectfully”.
1. Light: Oleander likes sunlight, so during the growing period it needs to be kept in a sunny place, otherwise it will produce few flowers and pale colors.
2. Temperature: Oleander should be planted in a wind-sheltered, sunny spot. In winter, move it indoors to protect it from freezing; a room temperature not lower than 0°C is sufficient. If the temperature is too high, it consumes nutrients, which is unfavorable for growth and flowering the following year. Where outdoor winter temperatures are high, soil can be mounded up around it to protect it from the cold.
3. Watering: Although oleander likes water, it fears waterlogging. On consecutive rainy days, the accumulated water in the pot should be poured out promptly to prevent root rot. Too much watering makes the leaves turn yellow and drop one after another, affecting flowering the next year. In spring and autumn, water according to the principle of "dry-wet alternation", keeping the potting soil moist. Summer is exactly the period of vigorous growth and flowering for oleander, so it needs more water; it is best to water once each morning and evening, and pay attention to frequently spraying and washing the branches and leaves to keep the leaf surface fresh and emerald green. Bring it indoors in mid-October; after bringing it indoors, watering should be controlled, and never let the amount of water be too large, otherwise it is prone to root rot and leaf drop, affecting growth the next year.
4. Fertilizing: Oleander likes fertilizer. From the time it is moved outdoors until the flowers fade (Frost's Descent), apply a thin liquid fertilizer once about every 20 days. After the Start of Autumn, oleander grows rapidly; at this time, apply fertilizer solution once about every 15 days until just before it is brought indoors.
5. Pruning: If oleander is left unpruned, the plant shape becomes too large, so when cultivating it in a clump form, the branches or trunks should be tidied up. Oleander has strong sprouting ability; if it is cut in the middle of a branch, many small branches will sprout from the cut, affecting the plant shape. Therefore, when pruning, in principle the cut must be made at the base of the branch.
6. Pests and diseases: Brown spot is an important disease on oleander. In the early stage of the disease, spray 50% benomyl wettable powder at 1000 times dilution, or 25% carbendazim wettable powder at 600 times dilution, or 36% thiophanate-methyl suspension concentrate at 500 times dilution.
Precautions:
Oleander has strong adaptability, and cultivation and management are relatively easy; whether planted in the ground or in pots, it is fairly undemanding. Where it is planted in the ground, transplanting should be done in spring, and heavy pruning should be carried out when transplanting. Pay attention to protection in winter. The branches and leaves are easily harmed by scale insects, so attention should be paid to control.
For potted oleander, in addition to requiring good drainage, it also needs sufficient fertility. After 1 to 2 years, repot once, and repotting should be done after pruning.
In spring, shaping and pruning are needed when new growth emerges. For water sprouts and weak, slender branches on the plant, they can be cut off from the base; for branches that are too dense in the inner canopy, part of them should also be thinned out, so that the branches are evenly distributed and the tree shape remains full.
Summer is the period of vigorous growth and flowering for oleander, when water demand is high. Besides watering once each morning and evening, if the potting soil looks too dry, an additional spraying should be given to prevent young branches from wilting and to avoid affecting the lifespan of the flowers.
After September, water should be withheld to inhibit continued growth of the plant, so that the branch tissues mature, nutrient accumulation increases, and safe overwintering is favored.
The overwintering temperature needs to be maintained at 8 to 10 degrees; below 0 degrees, it will shed its leaves. Oleander is a fertilizer-loving plant. For potted plants, besides applying sufficient base fertilizer, fertilizer should be top-dressed once a month during the growing period.