Vol. 7, Issue 1, Part L (2025)

Sustainable nutrient management is a critical challenge for modern agriculture. In smallholder systems, soil degradation and nutrient imbalance continue to limit productivity. This study investigated the dual dimensions of agronomic performance and educational outreach in promoting polyhalite-based fertilization practices. Polyhalite, a natural multi-nutrient mineral supplying potassium, calcium, magnesium, and sulfur, was evaluated through randomized complete block experiments over three cropping cycles. Results demonstrated that polyhalite significantly enhanced crop yields compared to conventional potassium chloride and control treatments, while simultaneously improving post-harvest soil sulfur, calcium, and magnesium status. Beyond agronomic outcomes, the study assessed farmer knowledge and adoption under different outreach models, including Farmer Field Schools, ICT-based dissemination, and printed extension materials. Statistical analyses confirmed that participatory and experiential learning models produced the highest adoption rates and knowledge gains, followed by digital platforms, with printed materials showing limited effectiveness. These findings highlight that while polyhalite offers substantial agronomic advantages, its successful adoption is contingent upon the effectiveness of educational interventions that bridge the knowledge-practice gap. The research concludes that integrating multi-nutrient fertilizers such as polyhalite with participatory outreach and digital extension strategies can accelerate sustainable fertilization practices, improve soil fertility management, and strengthen food security. Practical recommendations emphasize the scaling of farmer-centered extension approaches, incorporation of polyhalite into policy frameworks, and fostering of multi-stakeholder collaborations to ensure long-term adoption and agricultural resilience.