Smallholder farmers awareness, knowledge, and adoption of cover crops in agroecosystems in Sub-Saharan Africa: a narrative review

Smallholder farmers play a central role in food production across Sub-Saharan Africa (SSA), yet their production systems are increasingly constrained by soil degradation, climate variability, and declining resource availability. Climate-smart practices are increasingly promoted to boost productivity, resilience, and sustainability in smallholder systems. Among these practices, cover crops represent a field-level management option with potential to improve soil health, nutrient cycling, water retention, and climate resilience across diverse agro-ecological conditions. However, adoption of cover crops among smallholder farmers in SSA remains uneven and generally limited. Hence, understanding this gap requires an integrated assessment of how farmer awareness and knowledge interact with agronomic, socio-economic, and institutional constraints. This narrative review synthesises existing evidence on smallholder farmers’ awareness, knowledge, and adoption of cover crops in SSA by integrating findings on benefits, barriers, and enabling strategies. Relevant literature was identified through targeted searches of major academic databases. The review indicated that adoption is constrained by interacting factors, including limited access to extension services, labour demands, limited seed availability, and resource constraints among smallholder farmers. Emerging practices such as participatory on-farm trials, community-based learning approaches, and the promotion of multi-purpose cover crops that provide soil cover, nutrient inputs, and fodder are influencing adoption contexts in parts of the region. Therefore, presenting cover crops as multifunctional resources rather than competing land uses appears critical for improving their relevance within smallholder farming systems. This review identifies key leverage points for strengthening farmer awareness, extension support, and resource access to support wider and more sustained adoption of cover crops across SSA.