When will the wheat freeze?

The most suitable watering time is to freeze at night and disappear during the day. Generally, it starts around the light snow solar term in late June of 165438+ 10, and the average daily temperature is 7℃ ~ 8℃, and ends around 4℃ ~ 5℃.

1. Reasonably determine the time for pouring frozen water.

The most suitable watering time is "freezing at night and disappearing in the daytime", which generally starts around the light snow solar term in the end of 1654381October, when the average daily temperature is 7℃ ~ 8℃ and ends around 4℃ ~ 5℃. Irrigation too early, high temperature, large evaporation, can not play the role of heat preservation and moisture retention. Wheat fields with good growth will also lead to long wheat seedlings due to sufficient water and fertilizer, which will seriously lead to jointing before winter and easy to cause freezing injury. Irrigation is too late, the temperature is low, water is not easy to seep down, water is formed, the surface is frozen, and plants are easy to freeze to death after irrigation in winter. During the day, it should be held from 9 am to 4 pm.

2. Pour frozen water to see the moisture and seedling situation.

In order to keep suitable soil moisture when wheat turns green, soil moisture is generally insufficient. The moisture content of the surface soil in sandy land is lower than 65,438+06%, loam is lower than 65,438+08%, and clay is lower than 20%. The above indicators, the soil moisture is good, you can slow irrigation, you can not irrigation. Winter irrigation is not suitable for weak seedling wheat fields with few leaves, few roots, no tillers or few tillers, especially late sowing seedlings; For the wheat fields with large population and flourishing growth, if the soil moisture is good, winter irrigation can be postponed or not; Wheat fields with good soil moisture and sufficient fertilizer can be watered without overwintering water.

3. Irrigation should be appropriate.

The amount of irrigation should not be too large, and it is advisable to soak it thoroughly that day. It is forbidden to flood with accumulated water, which will form a frozen layer on the ground. The average irrigation amount per mu is 45 ~ 50 cubic meters. Winter irrigation combined with topdressing can be used in fertilizer-deficient wheat fields, and 5 ~ 8 kilograms of urea can be added per mu. Mow the ground in time after watering, conserve moisture, raise the ground temperature, and prevent hardening and cracking, ventilation and root injury, resulting in dead seedlings.