苹果树的花芽分化分为形态分化期—生理分化期—营养补充期三个阶段,头年五月下旬至六月上旬是形态分化期,大多数的花芽外型都是在此时形成的,而真正的生理分化和营养充实期则在中后期。中后期的营养不足往往出现第二年花而不实或冬剪时看似花芽,开春发出的却变成了大叶芽的现 Apple flower bud differentiation is divided into three stages of morphological differentiation - physiological differentiation - nutritional supplement, the first year from late May to early June is the morphological differentiation period, the majority of flower buds are formed at this time, The real physiological differentiation and nutrition enrichment period is in the late. In the latter part of the nutritional deficiencies often appear the second year of flowers and foolish winter or winter seemingly flower buds, issued in spring but has become a large bud now