What preparations are needed before sowing cotton
I. Land preparation and fertilization: On the basis of winter plowing and freezing of the soil, apply base fertilizer in spring by broadcasting 3 cubic meters of slow-release organic manure and 30 kg of quick-acting NPK compound fertilizer per mu, then plow again, harrow and level. After rain, harrow again to retain moisture and preserve soil moisture, and wait for sowing with sufficient moisture.
II. Seed preparation: (1) Variety selection. Choose disease-resistant and insect-resistant hybrid cotton varieties. Commonly used varieties include Yuzha 35, Zhongmian 47, Zhongmian 48, etc. (2) Seed selection. Choose seeds with high purity, plump grains, maturity, and high germination rate. (3) Sunning seeds. 7 days before sowing, choose sunny and warm weather and sun the seeds for 2–3 days to improve germination vigor and growth vigor. (4) Chemical seed dressing. Before sowing, mix insecticides and fungicides for seed dressing to effectively control underground pests and seedling-stage diseases.
III. Determination of sowing time: According to the climatic characteristics of our province, where the frost-free period gradually advances from north to south, the sowing time is set for April 20–25 in the northern Henan cotton region, April 15–20 in the central Henan cotton region, and April 10–15 in the southern Henan cotton region.
IV. Supplementing soil moisture before sowing and sowing with sufficient moisture: For cotton fields intercropped with wheat, because the direct sowing period of cotton coincides with the @#@245@#@ vigorous growth period, moisture consumption is severe, and the cotton rows are prone to moisture deficiency. During this period, if there is no rainfall, sprinkler irrigation should be used 3 days before direct sowing to supplement moisture. Moisture should be supplemented first and then sowing should be done; watering after sowing should be avoided. If sowing is done first and then watering is used to supplement moisture, it is very easy to cause low temperature and high humidity, which worsens seedling-stage diseases and leads to missing plants and broken rows, directly affecting yield.