How to grow Crossostephium chinense? Detailed guide to cultivation and care methods

Crossostephium chinense, also known as Qiai, Xueai and Xiangai, has a compact plant shape and silvery-white leaves like snow. It can be grown as a foliage potted plant for ornamental display or planted in the ground for landscaping. Because its roots and trunk are rugged and ancient-looking, and its branches and leaves are compact and naturally form clusters, it is also often used to make stump bonsai of various different styles.

???? Variety characteristics

Crossostephium chinense (Crossostephium chinense) is a perennial evergreen subshrub of the Asteraceae family and the genus Crossostephium (also called the genus Qiai). The main stem is upright, with many dense lateral branches; the branches grow upward, and the branch stems are light yellow-brown or gray-white, with longitudinal cracks on old trunks; the leaves are simple and alternate, clustered at the ends of branches, with leaves rectangular-spoon-shaped or rectangular-obovate, entire margins, and leaf colors gray-white or silver-white, egg-blue, and snow-blue.

???? Propagation methods

Methods such as sowing, layering and cuttings are used, among which cuttings are the most commonly used and are generally carried out in the growing season. The cuttings can use robust and well-developed branches; perennial old branches and current-year young branches are both acceptable, and length is not limited. In production, growing branches that affect the appearance are often cut for cuttings. The cutting bed can use river sand, perlite, vermiculite and other media with good drainage and air permeability. After inserting, water once thoroughly, then keep the soil and air moist, and provide appropriate shading to avoid exposure to the scorching sun. Roots form in about half a month, and after one month they can be divided and potted.

Seedlings of Crossostephium chinense are best planted in fertile soil, and a diluted decomposed liquid fertilizer should be applied once a week. Because it grows very quickly, attention should be paid to promptly pruning branches that affect the shape, concentrating nutrients and promoting the growth of the main trunk and main branches.

? Bonsai styling

Bonsai styling of Crossostephium chinense can be carried out during the growing period from April to October. In winter, because the branches are weak and easily broken, styling should not be done. Its styling can be processed as needed into different forms of bonsai, such as straight-trunk style, curved-trunk style, slanting-trunk style, double-trunk style, forest style, waterside style, cliff style and water-and-land style. The crown can adopt either a natural shape or a regular round disc shape; the styling method is mainly wiring, supplemented by pruning, with careful wiring and rough pruning. First use metal wire to wire the main trunk, main branches and lateral branches into the basic form, then prune appropriately to shape it. During styling, advantage can be taken of its characteristic of rapid wound healing by tearing off branches that affect the shape from the base together with the bark. After about one month, when the wound heals, that area becomes rugged and ancient-looking, with no trace of human intervention, achieving the artistic effect of "though man-made, it seems naturally formed" and having relatively high ornamental value.

The roots of Crossostephium chinense are old-looking and varied. When making bonsai, they can be raised above the soil surface according to styling needs to increase the bonsai's sense of antiquity. Like most stump bonsai, the root exposure of Crossostephium chinense bonsai must also be carried out gradually and cannot all be exposed at once, so as to avoid exposing too many fine roots, which would affect plant growth and, in severe cases, even lead to plant death.

???? Care and management

Crossostephium chinense is native to Taiwan, China, Fujian and other places in China. It likes a warm, humid and sunny environment, is slightly tolerant of partial shade, is not cold-tolerant, and fears waterlogging. During the growing season from April to October, it can be kept outdoors in a sunny place for care. Even in midsummer, shading is not necessary. If light is insufficient, branches and leaves will grow leggedly, the plant shape will become loose and not compact, and the leaf color will change from silver-white to light green, which will affect the ornamental effect. Crossostephium chinense has a well-developed root system and strong absorption capacity, and requires sufficient water and fertilizer supply during the growing season. It can be given a diluted decomposed cake fertilizer solution or other decomposed organic liquid fertilizer about once every 10 days. Usually, do not water unless the soil is dry; when watering, water thoroughly. Never give half-watering or allow waterlogging in the pot soil. When the air is dry, pay attention to spraying water on the plant to increase air humidity and avoid leaf scorch. During the rainy season, drain water promptly to prevent waterlogging; otherwise, waterlogging in the pot soil will cause root disease and rot.

In winter, move it indoors to a sunny place, restrict watering, stop fertilizing, and maintain a room temperature of 5°C to 10°C. If the temperature is too low, frost damage will occur, while if the temperature is too high, the plant will grow leggedly and affect its appearance.

Repot once every 1 to 2 years, generally in spring. The pot soil should be rich in humus, loose and fertile, and have good drainage. It can be prepared by mixing 5 parts humus soil, 3 parts garden soil, and 2 parts river sand and furnace slag. When repotting, do not damage too many roots. About 1/3 of the old soil can be removed, and the roots can be slightly pruned. After planting, water thoroughly and keep it under a shade shed for care. After the plant has recovered, it can be placed in a sunny place for normal management.

For Crossostephium chinense bonsai, pruning and shaping can be carried out once every spring. Cut overly long branches shorter, and cut off diseased and pest-damaged branches, dead branches, crossing and overlapping branches, winter leggy branches, and other branches that affect the beauty of the tree shape. This can not only maintain the beautiful bonsai tree shape and make the branches and trunk vigorous and rigid, but also prevent branch retreat caused by aging branches and trunks. Crossostephium chinense has strong sprouting ability. During the growing season, promptly remove excess buds on the branches and trunk, and pay attention to pinching and tipping to control the tree shape, promote new branches, and make the crown full and compact. Crossostephium chinense is a bonsai mainly valued for its foliage. Its yellow-green flowers are not highly ornamental and also have a strange odor, so when flower buds appear, they should be removed promptly to avoid consuming too many nutrients and causing the plant to age.

? Pest and disease control

The main insect pests of Crossostephium chinense are aphids, red spider mites and other damaging pests, which can be controlled by spraying with relevant pesticides. The main disease is root rot caused by poor soil permeability and waterlogging. It can be prevented by improving the cultivation environment. If disease occurs, promptly cut off the rotten root system, replace it with soil with good air permeability and replant, and provide appropriate shading to promote root recovery.