柑桔为常绿果树 ,一年多次抽梢 ,生长期长 ,结果量大 ,需肥量大 ,其总需肥量相当于落叶果树的两倍左右。树体营养具有累积效应 ,且不同生物学年龄时期和不同品种、不同砧木对营养需求不同。在营养平衡条件下可克服或缩小大小年结果变幅。花期和果实膨大期是营养需求高峰期 ,对 Citrus is an evergreen fruit tree, shoots many times a year, the growth period is long, the result is large, the amount of fertilizer required, the total amount of fertilizer required is equivalent to about two times the deciduous fruit trees. Tree nutrition has a cumulative effect, and different biological age and different varieties, different rootstocks have different nutrient requirements. In the case of nutritional balance can overcome or reduce the size of the annual change in amplitude. Flowering and fruit enlargement is the peak nutrition needs, right