Foliar NPKS application to cotton from full flowering to boll filling

Two field experiments were carried out at different locations to test the effect of NPKS sprays on cotton in addition to soil applied fertilizers. The differences in lint yield and average boll weight between treatments were not significant. Four foliar application (10 kg N, 1 kg P, 3 kg K and 0.5 kg S/ha/application) tended to increase the lint yield and the average boll weight in the location with the lower fertility. It seems that utilization of foliar nutrient application is dependent upon the availability of these nutrients in the soil. N was added mainly as urea, P and K as potassium polyphosphate and S as potassium or ammonium sulphate.