Fertilization method of winter rapeseed

Fertilization method of winter rapeseed

Winter rapeseed is a winter crop, and it is often a dry crop in flood and drought rotation. The soil is prone to lack of phosphorus. In addition, the soil temperature in the seedling stage is low, and the phosphorus supply capacity is weak. It is necessary to increase the application of phosphorus fertilizer. Experiments show that the appropriate ratio of nitrogen, phosphorus and potassium fertilizers in rapeseed production: N:P2O5:K2O is 1:0.6-0.8:0.5-0.6, and the average is 1:0.70:0.55. If the yield of rapeseed is 150 kg per mu, it generally requires 15 to 17 kg of nitrogen (N) per mu, and the average fertilization amount of N-P2O5-K2O is 16-11-9 (kg). The amount of fertilization should be adjusted appropriately according to the amount of organic fertilizer and the degree of soil deficiency.

1. Base fertilizer

Including 50% of total nitrogen fertilizer, and all phosphorus, potassium and farmyard manures. The amount of farmyard manure depends on the quality of the fertilizer, generally 3 to 5 tons per mu. Insufficient basal fertilizer, thin seedlings, even a large amount of topdressing is difficult to make up.

2. Top dressing

Divided into wax fertilizer (top-dressing in late seedling stage) and budding fertilizer (middle stage of bolting), each accounting for about 25% of the total amount of nitrogen fertilizer. If the rapeseed is weak, it can be topdressed in the early stage of bolting to avoid premature aging; if the growth is strong, it can be topdressed in the later stage of bolting when the sedge is 30 to 50 cm high to avoid crazy growth. The flowering period should be determined according to the growth of rapeseed. If top dressing is required, 50-70 kg of 1% urea or potassium dihydrogen phosphate solution can be sprayed during the flowering and podding period, which has better results.