Detailed Explanation of Oleander Cultivation and Management Methods and Technical Key Points
Oleander, also known as yangtao, bannianhong, or liuyetao, originated in Iran and India. It is an evergreen shrub or small tree of the Apocynaceae family. Dwarf types suitable for pot cultivation reach 60-80 cm in height, while tall types can grow to over 3 m. It blooms from late May each year, and the flowering period is extremely long, lasting until October. Flower colors include peach red, pink, yellow, white, and others, with peach red being the most common. The flowers are double-petaled and have a delicate fragrance. Every year during the flowering season, green leaves set off red flowers, gorgeous and elegant, offering both foliage and flowers to admire, combining the beauty of peach and bamboo.
Oleander has the function of protecting the environment and purifying the air, and has strong resistance to and absorption capacity for toxic gases such as chlorine, ammonium fluoride, and sulfur dioxide. As an ideal flower for beautifying the environment and purifying the air, it has been widely cultivated on green islands beside roads in major cities across our country and in greening areas of chemical plants, and is very popular among people.
Oleander likes fertilizer and fears waterlogging. It should be planted in a sunny, higher-elevation, well-drained, wind-sheltered spot. For pot cultivation, fertile and loose soil should be selected as the potting soil. Whether grown in the open ground or in pots, some base fertilizer should be applied to the soil before planting. Starting before flowering, apply a decomposed liquid fertilizer as a top dressing once every half month. In spring and autumn, water once every 3-5 days, and appropriately increase watering frequency in summer. If the weather is dry and hot and the plant is in a period of vigorous growth, it is best to water once every day and also spray water on the leaves. But during the rainy season, accumulated water should be drained promptly. In winter, water only when the soil becomes dry, and the amount of water should be small.
When cultivating this flower in the north, first, choose a wind-sheltered spot before planting; second, bank soil around the roots to protect against the cold before winter arrives; if the shoots are relatively tender, they should also be wrapped in straw to prevent freezing. For potted plants, move them indoors in winter to prevent freezing; for open-ground cultivation, in areas where low temperatures of minus 5°C frequently occur, the plants must also be dug up in late autumn, planted in pots, then moved into a low-temperature (around 3°C) indoor space, and in late April of the following year moved outdoors again to a sunny spot for planting.
Pruning is very necessary during the management of oleander. It has whorled leaves in threes, and after pruning, the branches naturally form a "three-fork, nine-top" shape.