Economic returns of alternative farming techniques in clove production: Evidence from Zanzibar

Abstract

Clove (Syzygium aromaticum) is a perennial smallholder crop widely grown in Zanzibar, Tanzania, but its production faces persistent challenges related to land scarcity, productivity and limited adoption of economically viable technologies. Identifying profitable production strategies is, therefore, essential for sustainable agricultural transformation in tropical disadvantaged cash-crop systems in sub-Saharan Africa (SSA). This study assessed and compared the economic returns, investment efficiency and financial viability of traditional cultivation, improved seedlings and intercropping in Zanzibar, Tanzania; using farm-level data from clove farmers. Gross-margin, partial-budget, break-even and sensitivity analyses were applied, alongside non-parametric tests of farmer-level economic outcomes. Improved seedlings generated the highest mean gross margins per farmer (US$1,603.90–1,820.03) and per hectare (US$636.19-721.89), exceeding intercropping and traditional cultivation. They also recorded the highest investment efficiency, with benefit–cost ratios of 3.74-4.31 and returns on investment of 274.03-330.83%. Intercropping generated the highest absolute gross margins and positive incremental net benefits of US$142,174.45-185,996.10, compared with US$18,685.50–23,386.90 for improved seedlings relative to traditional cultivation. All production systems remained financially viable under a combined 20% decline in revenue and 20% increase in variable costs. However, Kruskal–Wallis and pairwise Mann-Whitney tests found no statistically significant differences in farmer-level economic outcomes among the three techniques. Thus, observed economic advantages represent comparative associations rather than causal effects because farmers selected their production systems. Improved seedlings offer the strongest relative investment opportunity, while intercropping provides a viable diversification and land-use strategy. Strengthening access to quality-assured planting materials, extension, training, finance and market support could enhance the economic performance and resilience of smallholder clove production in Zanzibar.