This study aimed to determine the optimal concentration of liquid NPK fertilizer for the growth of oil palm seedlings in the main nursery stage. The study was conducted at the Rubber and Oil Palm Experimental Fields of PT. Pupuk Sriwidjaja, North Indralaya District, Ogan Ilir Regency, South Sumatra, located at coordinates 3º10'33"S and 104º40'26"E, from November 2025 to February 2026. The exp…