Bridging the Yield Gap: A Systems Analysis of the Constraints among Smallholder Maize Farmers in Monze, Zambia

This study analyses the maize yield gap among smallholder farmers in Monze District, Southern Province, Zambia. Using a sequential explanatory mixed-methods design, quantitative data were collected from 398 randomly selected farmers via structured questionnaires and crop-cut yield measurements. Qualitative data included six focus group discussions (n=48), 24 in-depth farmer interviews, and ten key informant interviews. Findings reveal a 64% yield gap (3.35 t/ha), with farmers averaging 1.85 t/ha against an attainable 5.2 t/ha. Decomposition attributed 60% to technology, 25% to efficiency, and 15% to resources. Multiple regression (R²=0.614, p<0.001) identified rainfall adequacy perception, fertilizer application rate, hybrid seed use, extension visits, credit access, and off-farm income as significant determinants. Climate variability (94%), lack of finance (88%), inadequate extension (81%), high input costs (78%), and declining soil fertility (69%) were foremost constraints. Credit access was a powerful enabler: farmers with credit were 3.45 times more likely to use fertilizer and 2.85 times more likely to adopt hybrid seed. The extension system was structurally incapacitated, with an officer-to-farmer ratio of 1:1,200; only 38% of farmers received a visit in the past year, and 53% rated extension services ineffective. Farmers preferred farmer-to-farmer learning (89%), village demonstration plots (84%), and locally tailored interventions (84%), with 73% willing to adopt improved practices given financial support. The study proposes a five-component intervention framework: (i) Climate-Smart Agriculture Promotion; (ii) Improved Financial Inclusion; (iii) Reformed Extension Service Delivery; (iv) Site-Specific Soil Fertility Management; and (v) Market Infrastructure and Access. It concludes that bridging Monze's maize yield gap requires a fundamental reimagining of the agricultural knowledge and innovation system, placing farmers at the centre of a participatory, adequately-resourced, context-specific process of sustainable intensification.