The morphological potencies of plants in creating a high yield are manifested the more fully, the better the growth of all their organs goes. The degree of manifestation of these potencies depends not only on internal causes, but also on the optimum of external conditions. Therefore, we studied the effects of mineral fertilizers on the growth and development of sugar corn plants during irrigation, which allowed us to establish the following patterns. Comparing the options with different doses and timing of mineral fertilizers, we see that there was a significant difference in the yield of commercial ears of sugar corn. In the control variant, with a single application of the calculated dose of mineral fertilizers, on average, over the years of research, the yield of commercial cobs reached 20.2 t /ha, including grain - 8.55 t/ ha. In the 3rd variant of the experiment, with fractional application of the calculated dose of mineral fertilizers, their effectiveness was the highest. Such an agricultural approach allowed to increase the yield of commercial cobs to 22.3 t /ha, including grain - 9.51 t / ha in comparison with the control variant. In the variant without fertilizers, the lack of nutrients in the soil during the sweeping of the panicle and the formation of grain turned out to be significant and caused a decrease in the yield of commercial cobs to 14.3 t / ha, including grain - 5.72 t / ha. The dynamics of nutrients in the soil depends on the doses of mineral fertilizers, their removal by the harvest, washing with irrigation water, precipitation, temperature conditions of the year, etc. Observations have shown that during the growing season of sweet corn, the intake of nutrients from the soil was uneven and increased with the age of plants.