2. Magnolia grandiflora is a famous ornamental tree species in China, which has been cultivated for more than 2500 years. Native to Jiangsu, Anhui, Zhejiang, Hunan, Hubei, Guizhou, Guangdong, Shanxi and other regions, it is also widely cultivated in Beijing and the south. The height of the tree can reach 25 meters and the diameter can reach 200 centimeters. The crown of young trees is narrow oval, and mature trees are wide oval or loose oval.
3. Climatic conditions: Magnolia is suitable for a wide temperature range, and can grow above -20~40℃. China is distributed from Xishuangbanna in Yunnan to Heilongjiang in the north. The optimum temperature zone of Magnolia grandiflora is from warm temperate zone to subtropical zone, with annual precipitation of 500 ~1850 mm. Extreme temperature also affects the growth of Magnolia grandiflora, especially its seedlings. Roots, buds or branches are vulnerable to freezing in winter, soil freezing and cold cracking wind. Exposure to high temperature and sunlight is easy to burn leaves, and long-term exposure to high temperature and strong light is easy to burn magnolia trunk and form ulcers. Under the scorching sun, the growth of seedlings has been stagnant for a long time. The inadaptability of Magnolia grandiflora to temperature is mainly manifested in its seedlings. The seedlings that grow vigorously in autumn and are not completely lignified are prone to freezing injury, resulting in the death of the above-ground parts.
4. Water and fertilizer conditions: Magnolia species are fleshy roots, with large flowers, lush leaves and large water demand. The most suitable place to live in nature is the mountain stream. Magnolia grandiflora planted in low-lying and waterlogged areas by artificial afforestation has poor growth, short branches and small leaves, and its plants are yellow. Long-term water accumulation is easy to cause root rot and root rot until the whole plant dies. Magnolia grandiflora grows rapidly, with a large number of flowers and fruits, flourishing in the growing period, which requires high soil fertility. The humus layer in the natural mountain stream soil layer is thick and rich in organic matter, which can fully meet the fertility requirements of Magnolia grandiflora growth.