This article presents the results of research concerning the phenological rhythms of growth and development, yield, chemical composition, nutritional value and productivity of annual crops depending on the timing of sowing. According to the results of measurements of the height of plants of annual crops for all sowing periods, the maximum height was reached for Sudanese grass: in its pure form - 175-214 cm, and mixed with legume components (with peas - 163-202 cm, with vetch - 160-207 cm) in the flowering phase. Studies have shown that in terms of average yield of green mass in all sowing periods, Sudanese grass surpasses all studied crops: in pure form - 182.7 - 273.3 c/ha, mixed with seed peas - 224.3 - 314.3 c/ha, mixed with spring vetch - 204.3 - 315.8 c/ha. According to the nutritional value of annual crops, a high content of digestible protein in 1 kg of dry matter was noted at the first and third sowing periods of Sudanese grass mixed with vetch - 182.4 -185.1 g, feed units -0.70-0.71. At all sowing periods on permafrost floodplain-turf and meadow-chernozem soils, crops of Sudanese grass in pure form and mixtures provided the highest yield of green mass - 182.7 - 315.8 c/ha, dry matter - 45.7 and 78.6 c/ha. The maximum yield of digestible protein at the first sowing period was recorded on mixed crops of Sudanese grass with vetch - 14.5 and peas - 14.1 c, with an exchange energy of 69.3 and 69.9 GJ/ha with a yield of feed units of 5.5 thousand per 1 ha.