Effect of Type and Concentration of Liquid Organic Fertilizer on the Growth of Oil Palm Seedlings (Elaeis guinensis Jacq) in Main Nursery on Subsoil Soil Layer

The main purpose of this study is to determine the effect of various types and concentrations of liquid organic fertilizers (POC) on the growth of oil palm seedlings in the lower layer of oil palm seedlings in the main nursery. This research was carried out at KP2 Instiper Yogyakarta in the villages of Kalikuning and Maguwoharjo, Special Region of Yogyakarta, from January 15 to April 15, 2025. The method applied was in the form of a two-factor factorial design with a Complete Random Design (RAL), using control and concentration of POC of 20%, 30%, and 40% as variables, with the type of POC (lamtoro, market waste, eco farming) as another factor. A total of 48 seedlings from 12 treatment combinations and 4 replicates were made. Variant analysis (ANOVA) at a significance level of 5% was used to detect differences, then further DMRT tests at the same level to determine the real differences. Root weight (wet and dry), leaf chlorophyll content, leaf area, and POC type and level showed significant interactions. The 40% market waste POC concentration is most optimal for wet root weight and chlorophyll content, while dry root weight is best at 30% and 20% concentrations. The largest leaf area is achieved with a concentration of 40% of POC waste markets, eco farming, and lamtoro. The three types of POC have a similar effect on plant height, stem diameter, root length, number of fronds, and weight of wet and dry shoots. A POC concentration of 40% indicates an advantage over 30%, 20%, and control in the number of fronds and the weight of shoots both wet and dry.