Sustainable intensification of smallholder maize production in northern Ghana: The case of cowpea living mulch technology.

Several agricultural technologies have been promoted to intensify smallholder farming systems in Ghana, but there is limited literature on sustainability assessment of these technologies. A 2‐year (2017–2018) on‐farm study was conducted to evaluate the sustainability of using cowpea [Vigna unguiculata (L.) Walp.] living mulch (CPLM) technology to intensify smallholder maize (Zea mays L.) production in northern Ghana. Four treatments (control, CPLM planted with maize on the same day, CPLM planted 1 week after maize, and CPLM planted 2 weeks after maize) were laid in RCBD with four replications per treatment. We used Sustainable Intensification Assessment Framework (SIAF) to assess the sustainability of the above treatments based on five domains (productivity, economic, environment, human, and social). We conducted the assessment in the following three steps: (1) measured selected indicators from the five SIAF domains, which were useful to answering research question; (2) converted measured values of the indicators into scores using a scale of 0–1; and (3) calculated sustainability index using geometric rules considering each SIAF domain as an edge of a pentagon. The sustainability indices for the CPLM increased by 143%–300% compared with the control treatment. The sustainability indices for the CPLM were >1, indicating better sustainability relative to the control treatment, which recorded sustainability index of <1. This suggests that smallholder farmers in northern Ghana and similar agroecologies can intercrop cowpea 1–2 weeks after planting maize as living mulch for better sustainability of their maize production and well‐being through its effect on yield, income, food security, nutrition, and gender equity. Core Ideas: The Sustainable Intensification Assessment Framework provides a systematic guide for assessing agricultural sustainability.Cowpea living mulch recorded higher sustainability scores relative to that of the control treatment.Cowpea living mulch sustainably has intensified smallholder maize production. [ABSTRACT FROM AUTHOR]