The article presents the results of studying the influence of tillage methods on the number of bacteria and fungi in the arable soil layer, nutrient indicators, and, consequently, the yield of Trifolium pratense. The purpose of the study is to determine how tillage affects the feeding regime and yield of Trifolium pratense. The research was conducted at the experimental field of the Educational and Scientific Research Center of Lviv National Environmental University. For the study of microorganisms in the arocenosis of meadow clover, soil samples were taken using a cylindrical drill from arable (0–20 cm) and sub-soil (20–40 cm) layers with an average weight of an individual sample of 300 g. For microbiological analysis, average samples from five individual samples were prepared. The isolation of the main agronomically useful groups of microorganisms from the soil was carried out by the method of microbiological sowing of soil extracts on solid nutrient media: for fungi – wort-agar, for bacteria – meat-peptone agar (MPA). The dilution of the soil extract for fungi and bacteria was, respectively, 1 : 1000; 1 : 100000. Microbiological seeding was performed in triplicate. The calculation of the total number of microorganisms in the soil was carried out by Tepper´s method. The yield of crops and the results of laboratory studies were processed by the method of variance analysis. The application of a tiered tillage allowed to increase the yield of Trifolium pratense green mass by 4.5 t·ha−1 (+17.0%) compared to the control (conventional plowing). It is established that tier ploughing with the PYA-4-40 plough promotes uniform distribution of nutrients in the arable soil layer and formation of homogeneous soil fertility. In such a soil environment, much more favorable conditions are created for the development of microflora and more intensive microbiological processes compared to the options of chisel and conventional (control) tillage, and, consequently, the formation of high yields of green Trifolium pratense.