The effects of phosphorus biofertilizers made from animal bones and sewage sludge ash and containing phosphate-solubilizing bacteria, Bacillus megaterium, were analyzed in a field experiment involving spring wheat. It was assumed that biofertilizers would be as effective as conventional phosphorus fertilizers such as superphosphate and phosphorite. The influence of biofertilizers on the growth rate of Bacillus megaterium bacteria in soil, the total counts of heterotrophic bacteria and fungi, the abundance of earthworms, and soil moisture and temperature were analyzed. Phosphorus biofertilizers containing ash and bones did not increase the abundance of Bacillus megaterium in soil, but unlike superphosphate they stabilized the strain’s population in the soil environment. The tested phosphate fertilizers and biofertilizers did not influence the total counts of heterotrophic bacteria and fungi in soil, the abundance of earthworms, soil moisture, or temperature.