Inorganic and organic fertilizer packages for growth acceleration and productivity enhancement on a four-year-old mature oil palm

Abstract

Fertilization is one of the efforts to increase the productivity of oil palm. This study aimed to determine the best combination of fertilizer packages and to find out the rate of organic fertilizers to reduce the use of inorganic fertilizers on 1st mature oil palm. This study used one factor of randomized complete block design that consisted of 11 treatment levels with three replications. The treatment levels were: control (P0), 1500 g urea+ 1000 g SP-36+ 1500 g KCl+ 50 g borate + 50 g CuSO4.5H2O per palm (P1), 3000 gurea + 2000 g SP-36 + 3000 g KCl + 50 g borate + 50 g CuSO4.5H2O per palm (P2), 4500 g urea + 3000 g SP-36 + 4500 g KCl + 50 g borate + 50 g CuSO4.5H2O per palm (P3), 2000 g NPK+ 50 g borate + 50 g CuSO4.5H2O per palm (P4), 4000 g NPK+ 50 g borate + 50 g CuSO4.5H2O per palm (P5), 6000 gNPK + 50 g borate + 50 g CuSO4.5H2O per palm (P6), 3000 g urea + 2000 g SP-36 + 3000 g KCl per palm (P7), 4000 g NPKper palm (P8), 3000 g urea + 2000 g SP-36 + 3000 g KCl per palm + 50 kg organic fertilizer per palm (P9), 3000 g urea + 2000 g SP-36 + 3000 g KCl per palm + 100 kg organic fertilizer per palm (P10). Fertilizer package (P3) is the best combination of fertilizer packages to increase the growth and yield such as trunk girth, bunch number, and productivity. Fertilizer package (P3) could increase the bunch number by 37.31% and productivity by 72.97% compared to control (P0). Application of 50 kg organic fertilizer year-1 (P9) could reduce by 30% of the use of a single package of inorganic fertilizers (P3).