How to fertilize sunflower reasonably

The fertilization technology of sunflower needs to absorb nitrogen (N) 4.59-6kg phosphorus (P2O5) 2.6-3.04kg potassium (K2O) 18.630kg from soil for every production of 100kg sunflower seeds. Phosphorus and potash fertilizers are mostly applied as base fertilizer or seed fertilizer, while nitrogen fertilizer is used as topdressing or 1Comp3 as base fertilizer 2amp3 as topdressing. The principle of fertilization is to apply sufficient basic fertilizer, heavy seed fertilizer and topdressing during the suitable period. The depth of ploughing is generally 13-25 cm, and the deeper the cultivated land is, the more yield is increased; the plots that cannot be turned should be fertilized by three ploughs, generally applying 25 cubic meters of farm manure per hectare, 100MUR 150 kg diammonium phosphate as base fertilizer, 100 kg urea, 50 kg potassium sulfate, or other fertilizer with equivalent nutrients. The seedlings were fixed in time when the seedlings were 2-3 pairs of true leaves. Before and after budding, the combination of ploughing and topdressing urea, 100 kg urea per hectare. The depth of fertilization is 8-10 cm, and the soil is cultivated to the base of the plant to meet the nitrogen supply at the peak of nitrogen uptake.