The word "apprentice" is a Chinese word. First, it refers to the phenomenon of excessive development of crop stems and leaves due to uncoordinated living conditions. Second, it refers to the length of apprenticeship.

Main reasons:

1. The reason of the variety or the seedling itself.

Such as peach, plum, pear, chestnut and other varieties are easy to grow white;

If there are problems with rootstocks, scions and seedling techniques of grafted seedlings, they will grow in vain.

Generally speaking, seedlings cultivated by seeds are easy to grow in vain.

2. Reasons for pruning and shaping

When young trees are reshaped, the big branches are left too little or clustered, the nutrient supply is too dense, the side branches are too few or cut too much, and the affiliation between the main branches and the side branches is not obvious;

When pruning in summer, do not pay attention to timely topping and tip control. When pruning in winter, we will cut the strong branches too heavy and cut off too many branchlets, which will also lead to excessive growth.

3. Improper fertilization

In youth, nitrogen fertilizer, chemical fertilizer or big fat water are applied, and organic fertilizer is rarely applied.

If we don't pay attention to the coordination of phosphorus and potassium fertilizers, soil moisture will be too much for a long time, which will also lead to excessive growth.