Potassium Fertilizer is Needed in Northern China

Results from soil testing over 8500 soil samples, detailed studies on 25 selected representative soils, greenhouse studies with 197 soils and results from 1350 field trials, conducted as part of the China-Canada Potash Agronomy Project (Phase III) in the last 5 years, indicated soil-K supplying capacity in northern China showed a notable regional distribution with a trend of a gradual decrease in soil-K supplying potential moving from the west to the east regions. Field experiments with various major crops indicated clearly that potassium fertilizer is needed in the northern region, especially for high yield and high quality crop production in the north east and north central regions.

Balanced fertilization with K vs farmer's practice on spring corn in Jilin

For spring corn in the northeast region, K application at an average rate of 133 kg/ha increased corn yields on average by 24.7%, one kg of K2O increase corn grain by 15.3 kg. The average ratio of N : P2O5 : K2O used for these field trials was 100 : 40 : 54.

For spring soybean in the northeast region, K application at an average rate of 162 kg/ha increased soybean yieldS on average by 14.7%, one kg of K2O increase soybean production by 3.4 kg. The average ratio of N : P2O5 : K2O used for these field trials was 100: 207:190.

Soybean showed signficant response to K in Heilongjiang

Winter wheat with K (right) and without K applied in Henan

For winter wheat in the north central region, K application at an average rate of 174 kg/ha increased wheat yield on average by 18.5%, one kg of K2O increased wheat grain by 5.9 kg. The average ratio of N : P2O5 : K2O used for these field trials was 100 : 62 : 91.

Corn in a fixed site trial in Hebei showed crop failure after 8 year soil K depletion

For summer corn in the north central region, K application at an average rate of 196 kg/ha increased corn yield on average by 19.4%, one kg of K2O increase corn grain by 7.8 kg. The average ratio of N : P2O5 : K2O used for these field trials was 100 : 55 : 92.

For details, please see paper by Jin Jiyun: "Soil Potassium Status and Potassium Fertilizer Use in Northern China".