Abstract
Food waste compost and its leachate serve as a promising organic soil amendment. Both products must be assessed in terms of their nutrient release rate to determine the adequate application rate, thereby avoiding soil contamination and plant damage. Detailed kinetic studies on the individual macronutrients, specifically nitrogen (N), phosphate (P), and potassium (K), release rates of the compost and leachate, as a function of their initial nutrient contents, and their effect on plant yield are limited. This study aims to determine the individual N, P, and K release rates of compost into plants fertigated with leachate to promote chilli yield. The N, P and K release rate constants by the compost obtained could aid in estimating the ideal formulation (compost loading ratio) for optimal chilli plant growth. Additional leachate treatment increases the N, P, and K release rate constant by 2- to 10-fold higher. With or without leachate, 50 % v/v reported the highest N, P and K release rate constant, 0.1503 g of N/kg of plant media /d, 0.0640 g of P/kg of plant media /d and 0.1775 g of K/kg of plant media/d, resulting in the highest plant yield (16 – 28 g of chillies/plant). Application of compost at a concentration higher than 50 % v/v, with and without leachate, resulted in a 10 % reduction in chilli yield and a 50 % reduction in chilli weight. The nutrient release rate constants derived from this study offer a practical guide for optimising food waste compost and leachate use in chilli cultivation, supporting sustainable nutrient recycling and improved organic farming prac