北方地区露地菠菜能否安全越冬,与越冬期的土壤水分状况有密切关系。北方冬季的气候温度低、风大,土壤水分的蒸发量也大,菠菜的根系常因干旱而死亡。菠菜田浇过“冻水”的土壤,上下层都有充足的水分,土壤结冰后,上下层土壤冻结在一起,地面无裂缝,可防止寒风直接侵袭根系,地温也不易散失。另外,浇“冻水”后,菠菜在早春返青时,土壤中仍含有充足的水分。黏重的土壤浇 Whether the open-field spinach can winter safely in northern China is closely related to the soil moisture condition in wintering period. Northern winter climate is low temperature, the wind, the evaporation of soil moisture is also large, spinach roots often die due to drought. Spinach field poured over “frozen water ” soil, the upper and lower layers have sufficient water, the soil after freezing, the upper and lower layers of soil frozen together, the ground without cracks, to prevent direct invasion of cold wind roots, ground temperature is not easy to lose. In addition, after pouring “frozen water”, the spinach still contains sufficient moisture in the spring when it returns to green in early spring. Sticky soil poured