What does the latest information on osmanthus include?
Osmanthus is the collective name for many trees of the genus Osmanthus in the family Oleaceae, also known as rock osmanthus, jiulixiang, jinsu, and so on. It is one of China's ten traditional famous flowers and an excellent garden tree species that combines ornamental and practical value, integrating greening, beautification and fragrance. It is widely used in garden construction, and there are many horticultural cultivars, the most representative being golden osmanthus, silver osmanthus, dan osmanthus and laurel. Among ancient Chinese poems about flowers, the number of works praising osmanthus is also quite considerable, and it has been deeply loved by Chinese people since ancient times.
Osmanthus is an evergreen tree or shrub, 3-5 m tall, up to 18 m at most, with grayish-brown bark and yellowish-brown branchlets. The leaves are leathery, elliptic, oblong-elliptic or elliptic-lanceolate, with the base gradually narrowed into a wedge shape or broadly wedge-shaped, entire or usually with fine serrations on the upper half, hairless on both surfaces, and the glands on both surfaces joined into small blister-like protrusions. The cymes are clustered in leaf axils, or nearly broom-like, with many flowers in each axil, the bracts broadly ovate, the flowers extremely fragrant, and the corolla yellow-white, pale yellow, yellow or orange-red. The fruit is oblique, elliptic, and purple-black. The flowering period is September to early October, and the fruiting period is March of the following year.
Osmanthus is adapted to subtropical climate regions, preferring warmth and humidity. The average temperature in growing areas is 14-28°C, the average July temperature is 24-28°C, the average January temperature is above 0°C, it can tolerate a minimum temperature of -13°C, and the most suitable growing temperature is 15-28°C. Humidity is extremely important to the growth and development of osmanthus, requiring an annual average humidity of 75-85% and annual precipitation of about 1000 mm. In particular, young plants and adult trees during flowering need more water. If drought occurs, it will affect flowering. Strong sunlight and shade are unfavorable to its growth, and generally 6-8 hours of light per day is required.
Osmanthus is native to the eastern section of the Himalayas in southwest China, and is also distributed in India, Nepal and Cambodia. Wild osmanthus grows in southwestern China, Sichuan, southern Shaanxi, Yunnan, Guangxi, Guangdong, Hunan, Hubei, Jiangxi, Anhui, Henan and other places. It is now widely planted in the Huai River basin and areas to the south. Its suitable growing area reaches as far north as the lower reaches of the Yellow River and as far south as Guangdong, Guangxi, Hainan and other places, and it has formed several nationally famous commercial osmanthus production bases in Lu'an, Anhui; Xianning, Hubei; Taoyuan, Hunan; Suzhou, Jiangsu; Guilin, Guangxi; Wuhan, Hubei; Hangzhou, Zhejiang and Chengdu, Sichuan.
Through long-term cultivation, natural hybridization and artificial selection, osmanthus has produced many cultivars. Through further investigation and sorting, 32 osmanthus cultivars have been preliminarily identified. By flower color, there are golden osmanthus, silver osmanthus and dan osmanthus. By leaf type, there are willow-leaf osmanthus, golden-fan osmanthus, dripping-yellow, sunflower-leaf, and firewood-handle yellow. By flowering period, there are August osmanthus, four-season osmanthus, month-by-month best, and so on.
Osmanthus is pale yellow-white, fragrant, and is used to extract aromatic oil and make osmanthus concrete, which can be used in food and cosmetics, can be made into cakes and candies, and can also be used to brew wine. Osmanthus is pungent in taste and can be used as medicine, with the flowers, fruits and roots used medicinally. Flowers are collected in autumn, fruits in spring, and roots in all four seasons, and are dried separately. The flowers are pungent in taste and warm in nature, with the effects of dispelling cold, breaking stagnation, resolving phlegm and relieving cough, and are used for toothache, cough and asthma with profuse phlegm, amenorrhea and abdominal pain, and other conditions. The fruit is pungent and sweet in taste and warm in nature, with the effects of warming the stomach, calming the liver and dispelling cold, and is used for deficiency-cold stomach pain. The root is sweet and slightly astringent in taste and neutral in nature, with the effects of dispelling wind-dampness and dispelling cold, and is used for rheumatic muscle and bone pain, low back pain, kidney-deficiency toothache, and other conditions.