从心叶开始卷曲包心直到收获是大白菜包心期,也是产量形成的关键时期。此时心叶生长迅速,重量增加很快,一般日长量达2两左右。因此,在管理上应满足植株对水肥的需求,以促进加速包心。追肥:从包心开始进行第二次追肥,每亩施尿素30—40斤。这时植株已封垅,为不碰伤叶片,可顺水追肥。到包心中期追第三 Curling the heart from the heart leaves until the harvest is the cabbage period, but also a key period of yield formation. At this point rapid growth of heart leaves, weight gain quickly, usually a total amount of about 2 or 2 days. Therefore, the management should meet the plant’s demand for water and fertilizer in order to promote accelerated inclusion. Top-dressing: From the heart of the second top dressing, 30-40 kg of urea per mu. At this time the plant has been sealed 垅, not to hurt the leaves, you can follow the water dressing. To the middle of the pack heart third