Application of natural NPK compound fertilizer on broccoli in organic agricultural systems

The use of organic fertilizers with high doses in nutrient management of organic farming systems needs to be reduced by adding natural NPK compound fertilizers. This study aims to test the effectiveness of natural NPK compound fertilizer combined with chicken manure in an organic farming system and to determine the optimum dose for the yield of broccoli. The study used a Randomized Complete Block Design, 7 treatments, and 4 replications. The treatment consisted of 5 doses of natural NPK compound fertilizer (200, 400, 600, 800, and 1000 kg/ha) combined with 10 tons/ha chicken manure, control, and 20 tons/ha chicken manure as standard treatment. The indicator plant used is broccoli. Agronomic observations were planted height aged 14, 30, and 50 days after planting, biomass, and yield of broccoli. Soil analysis after harvest i.e., pH, total-N, available P, and exchangeable K. The results showed that a natural NPK compound fertilizer dose of 400 kg/ha combined with chicken manure 10 tons/ha was effective in increasing the yield of broccoli by 6.83 tons/ha with an RAE value of 110% which was not significantly different from the standard treatment. The optimum dose of natural NPK compound fertilizer combined with chicken manure 10 tons/ha for a yield of broccoli is 420 kg/ha. The application of natural NPK compound fertilizer of 400 kg/ha can reduce the dose of chicken manure of 10 tons/ha on broccoli yield.