The research was conducted in 2003 - 2005 as a pot experiment on mineral soil to which ash doses of between 13.33 g and 800.0 g · pot-1 were supplied in proportions corresponding to the amounts of between 10 and 600 t · ha-1. The investigations aimed at learning the effect of diversified ash doses upon the content, ionic relations and the uptake of Mg, Ca, Na and P by maize. Macroelement concentrations in maize were diversified depending on the object and the plant part, fluctuating from 1.52 - 7.49 g Mg; 3.79 - 11.01 g Ca; 8.07 - 23.86 g K; 0.17 - 1.52 g Na; 1.23 - 3.16 g P · kg-1 d.m. It was found that with the growing ash dose the contents of Mg, Ca, K and Na in maize were increasing systematically, whereas P concentrations were decreasing. Magnesium and potassium content in maize aboveground parts met the requirements for a good quality fodder. The level of calcium, sodium and phosphorus in maize did not remain within the optimal range. A systematic increase in Mg uptake but a decline in P absorption by the aboveground parts were registered in maize in effect of growing ash doses.