We highlighted the results of studies on the influence of elements of growing technology and weather conditions on plant height and the area of the leaf surface of ryegrass perennial (Lolium perenne L.) varieties Andrian 80 and Svyatoshinsky. It was found that on the crops of perennial ryegrass higher plants are marked on variants with the adding of N60P60K60 and N60P60K60 + LCF of the Svyatoshinsky veriety - 66 cm and 51 cm in the Andriana 80 variety, which exceeds the area without fertilization by 16% and 24% respectively. It should be noticed that the highest plants of perennial ryegrass were in 2014: 39-59 cm in the Andriana 80 variety and 56-74 cm in the Svyatoshinsky variety, while the lowest plants were in 2015: 28-41 cm - Andriana 80 and 39-52 cm - the Svyatoshinsky variety. The results of the research indicate that the largest leafy apparatus in perennial ryegrass plants was formed during the release of plants into the stem and made for both varieties 15.3-31.4 thousand m2 /ha, regardless of fertilization and cover culture. Among the varieties of perennial ryegrass, area of the leaf surface was better formed in the Svyatoshinsky variety, which was 8.5 thousand m2 /ha (LSD05 = 5.4) greater than the Andriana 80 variety in the phase of the stem forming. According to the variants of cover culture in the same phase, a large area of leaves in perennial ryegrass varieties Svyatoshynsky and Andriana 80 was observed in the variant with the cover of the vetch-oat mixture. According to the fertilization options, a larger area of the leaf surface was in the variant with the adding of mineral fertilizers in the norm N60P60K60 and was within the range of Andriana 80 - 22,4-22,9 thousand m2 /ha, the variety Svyatoshinsky - 30,7-31,4 thousand m2 /ha depending on the cover culture. Consequently, high seed yield of herbs can only be obtained in crops, which dynamically form the optimal area of the leaf surface, capable of active work for a long time. Significant influence on the formation of the area of the leaf surface of the perennial ryegrass had a variety. Thus, in the Svyatoshinsky variety, in comparison with the Andriana 80 variety, in the phase of entering the stem, the average area of the leaf surface was greater by 8.5 thousand m2 /ha. In variants with fertilizer, the larger area of the leaf surface was for the adding of N60P60K60, N60P60K60 + LCF and N60P60K60 + LCF + B, and was within the range of 22.1-32.100 m2 /ha depending on the variety
ryegrass perennial, Svyatoshinsky and Andriana 80 varieties, fertilization, weather conditions, plant height, area of the leaf surface