Does intervention in African indigenous vegetables value chain improve production and welfare outcomes? Evidence from western Kenya

Abstract

African Indigenous Vegetables (AIVs) are increasingly recognized as essential for sustainable dietary diversification in the predominantly cereal-based staple diets. The AIVs also provide employment opportunities and generate income for the rural populations. Many initiatives by researchers and development agencies have promoted the AIVs value chains in Kenya. However, little evidence exists on impact of the initiatives on farm households. Several studies have examined impact of agricultural interventions based on observational data. The findings from such studies are likely to be influenced by unobserved attributes, resulting in a biased estimation of causal relationships between interventions and impacts. We conducted a clusterrandomized controlled trial to estimate the unbiased impacts of a multifaceted intervention that focused on production, consumption nutrition behavior change communication, and linking farmers to markets in selected AIV value chains (cowpea, spider plant, amaranth, nightshade, and slender leaf) in western Kenya. Using two waves of household panel data (2018 and 2021), we evaluated the impacts of the intervention on land area allocation to AIVs, total leaf production, AIVs income, and household dietary diversity Score (HDDS). The empirical estimation using descriptive statistics and analysis of covariance revealed that households that were exposed to the intervention significantly increased land area under AIVs by 38% (p < 0.01) and total leaf production by 46% (p < 0.05). At end line, the spider plant had the highest percentage increase (60%) in land area compared to the control group. However, there is no evidence of whether or not the intervention had an impact on AIVs income and HDDS. The study concludes that the hypothesis that the intervention was to have significant impact on AIV production, nutrition security and income had mixed results. We recommend that similar interventions include components to integrate the capacity of households to adapt to risks such as the COVID-19 pandemic and climate change. Further cost-benefit analysis is required for informed resource allocation. Designing and implementing policies that promote household access to input and output markets are likely to improve the performance of the AIV value chains and contribute to income and nutrition.