<![CDATA[Peanut (Arachis hypogaea L.) is a commodity with high economic value due to its high protein and fat content. Peanut productivity in West Kalimantan is still low compared to national productivity. Efforts to increase peanut production on peat soil include the application of liming and organic fertilizer. The objective of this study was to determine the best plant spacing and NPK fertilizer dose for the growth and yield of peanut on peat soil. The study was arranged using a Factorial Randomized Block Design. Plant spacing as the first factor consisted of 3 levels: J1 = 20 cm × 20 cm, J2 = 30 cm × 30 cm, J3 = 40 cm × 40 cm, and NPK fertilizer as the second factor consisted of 3 levels: N1 = 200 kg/ha, N2 = 250 kg/ha, N3 = 300 kg/ha, resulting in 9 treatment combinations replicated 3 times. Observed variables included root volume, root dry weight, number of pods, pod dry weight, seed dry weight, 100-seed weight, and seed dry weight per plot. The results showed that plant spacing and NPK fertilizer had no significant effect on all observed parameters, and there was no significant interaction between the two factors. Liming and organic fertilizer application increased soil pH from 4.34 to 5.25. The combination of 30 cm × 30 cm plant spacing with 200 kg/ha NPK fertilizer produced the highest seed dry weight per plot of 331.26 g, increasing by 64.2% compared to the lowest treatment, and was able to improve the growth and yield of peanut on peat soil. The combination of a 30 cm × 30 cm planting spacing with NPK fertilizer at 200 kg/ha produced the highest dry seed weight per plot, amounting to 331.26 g, which was 64.2% higher than the lowest treatment. This treatment was also able to improve the growth and yield of peanut plants grown on peat soil.The same treatment combination (30 cm × 30 cm spacing and 200 kg/ha NPK fertilizer) gave the best result, with dry seed productivity reaching 3.31 tons/ha, equivalent to 4.73 tons/ha of dry pods. ]]>
