In late autumn, winter and early spring and other low-temperature seasons, fertilization of crops should pay attention to the following points:
When the temperature of suitable ammonium bicarbonate is low, the ammonium bicarbonate is not easily decomposed and it is beneficial to increase the fertilizer utilization rate. Ammonium bicarbonate belongs to ammonium nitrogen fertilizer, which can be directly absorbed and utilized by crops after being applied to the soil and has a rapid fertilizer effect. It belongs to a typical “quick-effect fertilizer†and can provide nitrogen nutrition to crops in time. Tests have shown that topdressing ammonium bicarbonate in wheat fields in winter is 1 to 1.5 times more effective than in hot season.
Avoid application of urea urea belongs to ammonium ammonium fertilizer, can not be directly absorbed and utilized by the crop after being applied to the soil, need to be converted into ammonium nitrogen for root absorption. The rate of urea conversion mainly depends on the soil temperature at that time; under normal conditions, all urea applied to the soil is converted to ammonium nitrogen, which takes 7 to 10 days at a ground temperature of 10°C and 4 to 5 days at 20°C. Only takes 2 to 3 days at 30°C. It can be seen that the application of urea in the low temperature season tends to affect the growth of crops because of slower fertilizer efficiency.
The application of phosphorus and zinc fertilizers to the absorption of phosphorus and zinc is significantly affected by temperature and light. Low temperatures in autumn and winter, lack of light, easy to induce overwintering crops lack of phosphorus, zinc deficiency, should be appropriate increase in phosphate fertilizer and zinc fertilizer. In addition, phosphorus can enhance the plant's ability to resist cold, and increasing phosphate fertilizer helps prevent crop freezing.