Where is the latest distribution of the main osmanthus producing areas?
Osmanthus is the common name for many trees in the genus Osmanthus of the family Oleaceae, also known as rock osmanthus, Jiulixiang, golden millet, etc. 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. Its clear fragrance can dispel dust, and its strong scent can travel far. It has been deeply loved by the Chinese people since ancient times. Now let us take a look together at where osmanthus producing areas are!
Where are the osmanthus producing areas?
Osmanthus is native to the eastern section of the Himalayas in southwestern 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 cultivated in the Huaihe River basin and areas to its south. Its suitable growing area can reach as far north as the lower reaches of the Yellow River and as far south as Guangdong, Guangxi and Hainan. It has also 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.
The producing area environment of osmanthus
Osmanthus adapts to subtropical climate regions. It prefers warmth and moisture. In cultivation areas, the average temperature is 14-28°C, the average July temperature is 24-28°C, the average January temperature is above 0°C, it can withstand a minimum temperature of -13°C, and the most suitable growing temperature is 15-28°C. Humidity is extremely important for the growth and development of osmanthus. It requires an annual average humidity of 75-85% and annual precipitation of about 1000 mm. Especially during the young stage and when mature trees bloom, it needs more water. If it encounters drought, flowering will be affected. Strong sunlight and shade are unfavorable to its growth, and it generally requires 6-8 hours of light per day. It has strong stress resistance, tolerating both high temperatures and relatively low temperatures, and can overwinter outdoors in areas south of the Qinling Mountains and Huaihe River in China.
The four major cultivar groups of osmanthus
1. Four-season osmanthus cultivars: Four-season osmanthus is a clumping shrub, with a low tree form, short and dense branches, and a round spherical crown. New leaves are dark red, while mature leaves are green or yellow-green. The leaves are elliptical and broadly ovate, and the angle between the main vein and lateral veins is very large, nearly perpendicular. Flower buds are often solitary or 2-3 stacked together, blooming in batches from September each year to March of the following year. The fragrance is not as rich as that of silver osmanthus, golden osmanthus or red osmanthus. Common cultivars include large-leaf four-season osmanthus and small-leaf four-season osmanthus. Cultivars that bloom in all four seasons include Yueyuegui, Rixianggui, large-leaf Fodingzhu, and serrated-leaf four-season osmanthus.
2. Red osmanthus cultivar group: Red osmanthus is dioecious, with a round spherical crown, light gray bark that is relatively smooth, and sparse lenticels. The leaves are leathery, long elliptical or elliptical, with relatively flat leaf surfaces, revolute margins, entire margins, occasionally sparse teeth at the apex, a broadly wedge-shaped base, and a blunt or short-pointed apex. There are 8-10 pairs of lateral veins, the reticulate veins are obvious on both sides, and the petiole is 8-10 mm long. The flowers are orange-red, the corolla is slightly incurved, the fragrance is light, and the flowering period is from late September to early October. Cultivars include large-flower red osmanthus, serrated red osmanthus, cinnabar red osmanthus, and broad-leaf red.
3. Golden osmanthus cultivar group: Golden osmanthus has a round spherical crown, strong tree vigor, upright branches, and is very compact. The bark is gray, the lenticels are round or elliptical, and the spring shoots are relatively thick. The leaves are dark green, elliptical, with uneven leaf surfaces and slightly wavy margins. The flowers are yellow, strongly fragrant, and do not set fruit. They bloom in autumn, and the flowers range from pale lemon yellow to golden yellow. Cultivars include large-flower golden osmanthus, large-leaf yellow, Huangchuan golden osmanthus, late golden osmanthus, round-leaf golden osmanthus, Xianning late osmanthus, ball osmanthus, round-petal golden osmanthus, willow-leaf Su osmanthus, Jinshi osmanthus, and wavy-leaf golden osmanthus.
4. Silver osmanthus cultivar group: Silver osmanthus has a round spherical crown, spreading large branches, dense branches and leaves, and good growth. The bark is light gray, and the lenticels are numerous and large, shaped like snowflakes, very obvious. The leaves are green or dark green, long elliptical or elliptical, relatively broad and thick, and the leaf surfaces are relatively flat. It blooms in early to mid-September, with flowers from milky yellow to lemon yellow, rich fragrance, and does not set fruit after flowering. It blooms in autumn. Cultivars include broad-leaf seed silver osmanthus, willow-leaf silver osmanthus, hard-leaf silver osmanthus, seed silver osmanthus, Jiulong osmanthus, early silver osmanthus, late silver osmanthus, Baijie, pure white silver osmanthus, and Qingshan silver osmanthus.