DEVELOPMENT AND EFFICACY EVALUATION OF A FORTIFIED BLENDED LOCAL FERTILIZER FROM WASTE-DERIVED RESOURCES FOR MAIZE CULTIVATION IN MALAWI

The global fertilizer crisis, exacerbated by geopolitical tensions and supply chain disruptions, has severely impacted food security in import-dependent nations like Malawi. This study pioneers the development and field evaluation of a novel, low-cost fortified blended fertilizer (FBF) formulated primarily from locally abundant waste streams: sanitized powdered sewage, wood ash, agricultural lime, and processed human urine. To address immediate nutrient availability gaps inherent in organic sources, the base mixture was strategically fortified with minimal quantities of commercial NPK (for basal application) and urea (for top-dressing). A comprehensive mixed-methods approach was employed, encompassing formulation chemistry, soil science, and agronomic trials. Laboratory soil analysis post-application revealed markedly elevated nutrient concentrations (N: 308–359 mg/kg, P: 432–503 mg/kg, K: 988–1150 mg/kg) and a high composite fertility index (3397–3953 mg/kg). Field trials demonstrated that maize cultivated with the FBF achieved robust growth, with no visual symptoms of nutrient deficiency or toxicity, yielding an average of 3.2 tons per hectare which a significant improvement over non-fertilized controls. Key soil health indicators, including a suitable slightly acidic pH (5.7–6.1) and elevated Electrical Conductivity (EC), were monitored, with the latter prompting recommendations for irrigation management. The results robustly indicate that this waste-valorizing fertilizer model presents a viable, sustainable, and economically accessible alternative to conventional inorganic fertilizers. It aligns with circular economy principles, reduces environmental footprints, and enhances local resilience, offering a scalable solution for improving food security in Malawi and analogous sub-Saharan African contexts.