The flowers are white, fragrant, 15-20 cm in diameter; Perianth segments 9-12, thick fleshy, obovate, 6-10 cm long, 5-7 cm wide; Stamens about 2 cm long, filaments flat, purple, anthers inward, connectives protruding into a short tip; Pistil group is elliptic, densely covered with long hairs; The carpel is ovoid, 1-1.5 cm long, and the style is curly.
Aggregate fruit cylindrical oblong or ovoid, 7-10 cm long, 4-5 cm in diameter, densely covered with brown or grayish yellow hairs; Follicles dehiscent, abaxially round, with a long beak on the outside; The seed is nearly ovoid or ovoid, about 14 mm long and 6 mm in diameter. The testa is red. The seed without the testa is extended into a short neck. Flowering from May to June, fruiting from September to October.
It is native to southeast North America. It is cultivated in cities to the south of the Yangtze River basin in China. It is also cultivated in Lanzhou and Beijing parks. This species is widely cultivated, with more than 150 cultivated lines. Weak positive, like warm and humid climate, anti pollution, not resistant to alkali soil. The seedlings are quite shade tolerant. It likes warm and humid climate. It is relatively cold resistant and can withstand short-term low temperature of - 19 degrees. It grows well in fertile, deep, moist acid or neutral soil with good drainage. Its roots are deep and wide, and it is quite resistant to wind. Few diseases and pests. The growth rate is medium, and the seedling growth is slow, and the growth gradually accelerates after 10 years.
Cultivated soil is usually selected with strong water holding capacity, loose texture and free of diseases and pests. Generally, 60% yellow mud is mixed with 40% rice bran ash, vermiculite, expanded perlite, or fully decomposed cottonseed crumbs, textile crumbs, and mushroom bed soil are used. The water content should be appropriate, and it should be squeezed out with water when holding tightly. In order to make the wound heal quickly and root early, the upper part of the wound can be coated with 5/10000 naphthylacetic acid solution, and then coated with culture soil after slightly drying. If the layering starts to take root in April and June, it is generally necessary to lower the tree in late September, and inspection should be carried out in July and August. If the cultivated soil is dry, a syringe can be used to fill it with water.
The branches and trunks are easy to be burnt by the hot sun, so that the skin will burst and wither, causing serious damage. Whether young trees, new plants or forest trees, if the branches and trunks are exposed to the hot sun in summer, they should be wrapped with straw rope or coated with lime emulsion as soon as possible to avoid incurable losses. The lotus magnolia has well proportioned branches and upright tree shape. It is allowed to grow naturally rather than pruning; If the grafted seedlings with Magnolia as the rootstock often sprout rootstock buds from the root neck, they should be removed in time. There are very few diseases and pests of Magnolia nucifera. In April, attention should be paid to preventing leaf rollers from harming buds, leaves and flower buds. 1000 times 98% crystal trichlorfon can be sprayed 2-3 times.
The size of the soil ball is the key to the success of transplanting Magnolia grandiflora. In East China, the diameter of the soil ball is generally 8 to 10 times the DBH of the tree, so that the root system is less damaged and the tree vigor is easy to recover. If the soil ball is too small, the root system will be seriously damaged, causing difficulty in absorbing water and affecting the survival of trees. The earth ball shall be excavated into a gyroscopic shape rather than a plate shape or a cone shape. The earth ball shall be tightly tied with straw rope to avoid loosening during transportation.
