What are the climatic characteristics of Grain Rain? What is the impact on agriculture?

Grain Rain every year on April 20th or 2 1 day, when the sun is located at 30 degrees of the yellow meridian, it is the Grain Rain, which is the last solar term in spring. As the saying goes, "Snow breaks in Qingming Festival and frost breaks in Grain Rain". After Tomb-Sweeping Day, the rainfall increased, which was beneficial to grain growth, and it can be said that "rain gives birth to a hundred valleys". After Grain Rain, the temperature rose rapidly, and the average temperature in most parts of the country was above 12 degrees. In the "Poplar bloom" south of the Yangtze River, tea farmers gather tea to make tea, agricultural production plows crops in spring, and Koharu harvests crops, reaching a busy period. In late April, the average temperature in North China rose to 65438 07.2 degrees, and the rainfall increased to 36 mm, which was very beneficial to the emergence and growth of wheat and spring-sown crops. Before and after Grain Rain, wheat should be well fertilized at booting stage, rape leaves should be sprayed with fertilizer once, and cotton should be planted quickly. At the same time, spring fields should dredge ditches, manage soil moisture and prevent waterlogging. In the northeast, there is a saying that "Grain Rain farmed before and after". The so-called "field" mainly refers to the cultivation of crops such as sorghum and corn. Compared with the Yellow River Basin, the solar term in the northeast is relatively late, and the rainfall in Grain Rain is not as much as that in the south. Moreover, the cold and warm air flow is "seesaw" locally, which is prone to strong winds, dust and other weather.