In a 10-treatment microfield experiment, carried out on a strongly acidic sod-podzolic soil, which was calcified by dolomite with different particle size, the dynamics of mobile (plant-accessible) iron content was traced. It was revealed that liming led to a decrease in the mobility of soil iron. The ameliorant with larger particle size was less effective on the investigated parameter. The studied fractions of dolomite were divided into 3 groups according to their effect on the change in the content of mobile soil iron. In the treatments meliorated by dolomite fractions of 0.25–1, 1–3, and 3–5 mm in a scientifically substantiated dose, the average rates of change in the content of this element throughout the study period did not significantly differ from zero. In the treatment without liming and the treatments reclaimed by limestone flour (MI) and dolomite flour (DM), a significant positive dynamics of this indicator was observed (tendency to an increase in the average concentration of iron over 10 years of e