Predicting the responsiveness of pasture to potassium fertiliser in Victoria

Abstract

A quantitative model has been developed from the results of 180 field experiments in Victoria, to estimate pasture responses to rates of potassium fertiliser, where the amount of soil potassium extracted by 0.05 mol/L HCl, soil texture and annual rainfall are known. Available soil potassium accounted for 42% of the variation in pasture responses. Soil texture did not affect the magnitude of the response to applied potassium, but there was an apparent affect of soil texture on the curvature of the response curve. Potassium fertiliser recommendations in Victoria can now be based on the results of 180 field experiments which measured the response of pasture to potassium fertiliser at different locations and years, under a range of management conditions.