The study aimed to evaluate the formation and utilization of productive soil moisture reserves in short-rotation cereal–sugar beet crop rotations of the Forest-Steppe zone under conditions of increasing hydrothermal variability. A long-term stationary field experiment (2020–2025) was conducted to assess precipitation distribution, soil moisture dynamics within the 0–150 cm layer, total crop water consumption, yield performance, and the water consumption coefficient (WCC) under different fertilization systems. The highest depletion of productive soil moisture was recorded under clover (205–212 mm) and sugar beet (up to 132 mm under 40 t ha⁻¹ manure + N100P90K90), reflecting intensive moisture extraction from deeper soil horizons (50–150 cm). In contrast, winter wheat primarily utilized moisture from the 0–30 cm layer, and soil moisture reserves at harvest exceeded sowing values by 3–50 mm. Total crop water consumption ranged from 2193 to 5487 m³ ha⁻¹. Sugar beet demonstrated the highest productivity and water use efficiency: root yield reached 42.8 t ha⁻¹, total biomass 62.6 t ha⁻¹, with a WCC of 90 m³ t⁻¹ under organo-mineral fertilization. Sunflower consumed 4220–4400 m³ ha⁻¹ with grain WCC values of 1137–1491 m³ t⁻¹. Leguminous crops showed elevated WCC values under unfertilized conditions, reaching 3027 m³ t⁻¹ for spring vetch grain. Mineral (N53P42K42) and organo-mineral (6.7 t ha⁻¹ manure + N53P42K42) increased crop yields and reduced WCC across the crop rotations. The cereal–fodder–tilled crop rotation demonstrated the most efficient water use WCC (118 m³ t⁻¹ for total biomass and 160 m³ t⁻¹ for grain), whereas the tilled rotation exhibited the highest soil moisture depletion (up to 107 mm). Inter-vegetation precipitation (48–394 mm) significantly influenced initial soil moisture reserves and subsequent crop performance, confirming its critical role in agroecosystem water balance formation.