To manage spring care of late-sown wheat well, it should be carried out according to its characteristics.

Every year there are always some wheat fields sown relatively late. The characteristics of late-sown wheat: First, the tillering period is short. Because sowing is late and emergence is late, there is no tillering period before winter, and the spring tillering period is generally less than 20 days, so the number of tillers per plant is small, and the tillering roots are also few, which is the main reason for slow growth in spring. Second, the underground stem is short. Because it is under low temperature before winter, the tillering node grows slowly and is buried deep in the soil, which affects rapid emergence and early seedling development in spring. Third, the internodes are short. According to observations, the first and second basal internodes of late-sown wheat are only about 2/3 the length of those of timely sown wheat, so late-sown wheat plants are short and are not prone to lodging later. Based on the above characteristics of late-sown wheat, the following 3 points should be mainly done well in spring management:

1. In early spring, hoe and scarify more and finely to raise soil temperature and promote early seedling development. The key time for hoeing and scarifying to increase temperature and promote early seedling development is the “freeze-thaw period” when it freezes at night and thaws during the day. During this period, hoeing thoroughly and evenly to raise soil temperature and striving to raise the daytime temperature above the effective temperature can promote early seedling development. According to measurements, wheat fields that are hoed and scarified are generally 0.5-0.8 degrees C warmer during the day than wheat fields where the soil is loosened but not hoed, and this can promote green-up 3-5 days earlier.

2. Remove soil and clear the ridges to increase temperature and capture light, promoting early and rapid tiller development. Removing soil and clearing ridges in early spring can increase the soil temperature at the tillering node, increase the light-receiving area of wheat seedlings, and promote early emergence and growth of tillers. The effect is especially obvious for wheat fields sown deeper and with heavier soil coverage over the seedlings. Experiments show that after clearing the ridges, the soil temperature at the tillering node increases by 1.6-2.1 degrees C compared with not clearing the ridges, each plant can grow one more leaf and increase by one more tiller, and each mu can produce 50,000-80,000 more ears, significantly increasing yield.

3. Apply water and fertilizer heavily at the jointing stage to strive for more ears and promote larger ears. Because late-sown wheat seedlings are small and have few roots in early spring, their demand for water and fertilizer is not very urgent. Therefore, unless it is very dry, do not water early, so as to avoid lowering soil temperature, compacting the soil, and affecting development. Practice has proved that the best benefit period for the first water and fertilizer in spring is around the “jointing stage.” At the same time, in combination with watering, apply 50-60 jin of ammonium bicarbonate and 30-40 jin of phosphate fertilizer per mu, which can achieve the double effect of increasing the number of ears per mu and increasing the number of grains per ear.