Cultivation techniques of "oleander"

Oleander (Neriummdcum), also known as willow peach, is red for half a year. Oleaceae, genus oleander. It is named because its flowers are like peaches and leaves are like bamboo. The flowers and colors are beautiful, or pink, like peach blossoms, rich and gorgeous, or pure white, as clean as snow, crystal clear, which has been appreciated by people since ancient times. Cultivated everywhere, it is an excellent flowering shrub that blossoms in summer and autumn and can resist pollution.

(1) morphological characteristics and varieties

Large evergreen shrub, plant height up to 4 m ~ 5 m, crown spreading, branches erect and smooth, tufted, young shoots angled, strong branching, mostly trichotomous growth. Leaves lanceolate, often 3-4 verticillate, branches in the middle and lower parts of many opposite, thick leathery, midrib obvious, entire, with a short handle, branches and leaves have a small amount of milk. Cymes terminal, Corolla funnelform, 5-lobed, wrinkled on petals, lobes twisted to the right, pink to crimson, mostly double and semidouble. The florescence is long, from June to October, there are flowers one after another. There are many varieties of horticulture, such as white oleander, safflower oleander and so on.

(2) Ecological habits

Oleander originated in India, Iran, Afghanistan, like warm and humid climate, cold tolerance is not strong, in the south of the Yangtze River basin in China can be planted in the open, but in Nanjing sometimes branches and leaves freeze-withered, seedlings even freeze to death. In the north, you can only watch it in pots and spend the winter indoors. The cold tolerance of white flower variety is slightly stronger than that of safflower variety. Oleander is not resistant to water and moisture, so it is required to choose a place with high dryness and good drainage. Like light like fertilizer, can also adapt to a more shady environment, but shaded planting, less flowers and light color. It has strong resistance to air pollution, strong resistance to toxic gases such as sulfur dioxide, chlorine, smoke and dust, and strong absorption capacity, so it is an excellent tree species for greening and decoration of industrial, mining and railway platforms. The ability of sprouting and tillering is strong, and the tree is easy to recover after being damaged.

(3) methods of reproduction

Cuttings are mainly propagated, and they can also be divided and striped. Cutting can be carried out in both spring and summer. Soak the base of cuttings in clean water for about 10 days, keep them fresh, take root ahead of time after insertion, and the survival rate is also high. The specific method is that the 1-to 2-year-old branches cut in spring are cut into stem segments of 15 cm ~ 20 cm, about 20 are tied up into a bundle, soaked in clean water, and the water depth is 3 for the stem segment, the water at the same temperature is changed once every 2 days, the temperature is controlled at 20C~25C, and adventitious roots can be cut when adventitious roots are found in the immersed part. When cutting, you should make holes with bamboo chopsticks in the soil so as not to damage the adventitious roots. Because of the strong sprouting ability at the base of the old stem of oleander, a large number of twigs are often produced, which can be fully used for softwood cuttings in summer. Select semi-Lignification degree cuttings, retain the top 3 leaflets, insert in the matrix, pay attention to timely shading and water management, the survival rate is also very high. When pressing and reproducing, first cut the buried part or cut it in the ring, bury it in the soil, cut off the mother in about 2 months, and transplant it with soil in the coming year.

(4) cultivation techniques

Oleander has strong adaptability, easy cultivation and management, and is relatively extensive no matter in the field or in the pot. In the place where the ground is planted, transplanting should be carried out in spring, and re-cutting should be carried out when transplanting. Pay attention to protection in winter. Branches and leaves are vulnerable to scale insects, so attention should be paid to prevention and control.

Potted oleander requires not only good drainage, but also sufficient fertility. Spring germination needs shaping and pruning, the overgrown branches and slender branches in the plant can be cut from the base, and the dense branches in the inner chamber should also be thinned to make the branches distributed evenly and keep the tree shape plump. After 1 ~ 2 years, the basin was changed once, and the basin should be changed after pruning. Summer is the period of vigorous growth and flowering of oleander, which requires a lot of water. In addition to watering each day in the morning and evening, if the pot soil is too dry, one more spray should be added to prevent the twigs from wilting and affecting the flower life. After September, water should be deducted to inhibit the continued growth of the plant, make the branch tissue mature and increase the accumulation of nutrients in order to survive the winter safely. The overwintering temperature should be maintained at 8C~10C, below 0C, that is, the leaves will fall.

Oleander is a fertilizer-loving plant, which should be applied once a month during the growing period in addition to sufficient basal fertilizer.

(5) viewing and application

In the season of few flowers in summer, oleander blossoms for nearly 4 months, which is a rare summer flowering tree species, which can be planted in the left and right sides of buildings, parks, green spaces, roadsides, poolsides and other areas, and is more suitable for anti-pollution planting in industrial and mining areas and along the railway.

Stems and leaves are poisonous and should be paid attention to when pruning and cutting.