Hartono et al. 2026. APPLICATION OF LIQUID UREA FERTILIZER TO LEAVES IN OPTIMIZING VEGETATIVE LEAF GROWTH IN PLANTS THAT HAVE NOT PRODUCED IN PTPN IV REGIONAL 1 RANTAU PRAPAT GARDEN. International Journal of Social Science, Educational, Economics, Agriculture Research and Technology (IJSET). 5, 4 (Mar. 2026), 2029–2033.