The mechanism of potassium retention in Nigerian soils appears complex. In order to overcome the effect of K fixation in the soils, the use of K fertiliser factor was proposed by many workers. This, to some extent, had proved to be successful. It is imperative to note that K retention in Nigerian soils is influenced by pH, organic matter, parent material, type and content of clay, Al2O3, concentration of K added to soil and moisture content. However, significant responses of crops to K application to Nigerian soils had been documented.
