大白菜种植早时,往往只长叶,不包心,菜球小,产量低,主要原因是天气温度高,雨水多,或高温土地失水过快,以及病虫发生为害严重,特别是软腐病、干心病、霜霉病、白粉病、病毒病、蚜虫、菜青虫等危害;施肥不当,如氮肥过多、磷钾肥不足、水分供应不均匀,也是造成大白菜不包心的主要原因。如果采取下列技术措施加强管理,可以促使其包心结球。1.增施磷钾肥在大白菜种植25～30天后,开始增 The early planting of Chinese cabbage is often only long leaves, unwrapped, small cabbage, low yield, mainly due to the weather is high temperature, rain, or high temperature water loss of land too fast, as well as pests and diseases serious damage, especially soft Rot, dry heart disease, downy mildew, powdery mildew, virus disease, aphids, cabbage and other hazards; improper fertilization, such as excessive nitrogen fertilizer, phosphorus and potassium inadequate water supply is uneven, but also caused the main reason for cabbage . If you take the following technical measures to strengthen management, you can make it a tight knot. 1. Increased phosphorus and potassium in cabbage planted in 25 to 30 days, began to increase