Magnolia likes fat, but avoid big fat; Generally, applying fertilizer twice in the growth period is beneficial to flower bud differentiation and promoting growth. Once in early spring and once in May-June. Fertilizers are mostly fully decomposed organic fertilizers. Newly planted saplings don't need fertilization until the leaves fall or the next spring. The root system of Magnolia grandiflora is fleshy and cannot tolerate stagnant water. It is advisable to keep the soil slightly wet at flowering stage. After autumn, it is necessary to reduce watering, delay the rooting of Magnolia grandiflora, and promote the maturity of branches to facilitate wintering. Generally, it is not watered in winter, and only once the soil is too dry.
Magnolia branches have poor wound healing ability and are generally not trimmed. However, in order to make the tree shape reasonable, in the early stage of leaf opening, long branches, dead branches, pest branches and branches that hinder the beauty of the tree shape should still be cut off. In addition, after the flowers wither, if no seeds are left, the residual flowers and fruit ears should be cut off to avoid consuming nutrients and affecting the next year's flowering.
There are many kinds of magnolia in the ground, and potted plants should be cultivated into piles.
For your reference.