The scientific work analyzes experimental data on the cultivation of potatoes and rapeseed using elements of biologization in conditions of Ryazan region. Two-year studies have been carried out to study the effect of developed mushroom compost on the yield of potato tubers and rape of various varieties cultivated on dark gray forest soils of Ryazan region. The use of spent mushroom compost is a promising technique that allows to increase the productivity of crops and obtain environmentally friendly products. When cultivating potatoes and spring rape, first, bare fallow was used as a precursor, and then the introduction of 84 t/ha of fresh mushroom compost for the main processing of potatoes and 80 t/ha for spring rape, immediately after harvesting mushrooms in the form of developed blocks. In the second option, 95 t/ha of mushroom compost was used for potatoes and 89 t/ha was used for spring rape, after a year of storage of spent mushroom blocks. As a result of the use of two types of mushroom compost, the foliage of plants improved: on average, the largest increase in leaves was obtained in the option with fresh compost. Its use immediately after harvesting mushrooms exceeded the control by 12.8%, and the use of compost after a year of storage caused 7.6% increase. The highest average marketability of tubers for all varieties was noted in the option with fresh mushroom compost and averaged 80.8% for all varieties, which was 9.1% more than the control. The productivity of spring rape seeds increased when using mushroom compost as a fertilizer. The introduction of fresh compost under the main tillage increased the rape productivity by 2.9 dt/ha, and rotted compost by 1.9 dt/ha compared with the control. For all varieties of potatoes, the yield with fresh mushroom compost increased by 37.8 dt/ha or 20.1% compared to the control, and for the variant after a year storage of mushroom compost, the yield increased by 23.8 dt/ha or 11.3 %.