The paper presents an analysis of the role of two forms of social capital – linking and bonding – on two key farm outcomes: on-farm crop diversity and household wellbeing. Where market transactions are limited, social capital is an important household asset for accessing seed and channelling information. The study is set in a drought-prone region of Ethiopia, with high rates of food insecurity and dependency on agriculture for livelihoods. The region is very rich in crop genetic diversity, particularly for sorghum. The data were collected for a production year that experienced a major drought shock. Results of the analysis indicate that social capital is an important determinant of farm level diversity and wellbeing, with opposing effects related to the two different forms of social capital. This suggests possible trade-offs between the two forms of social capital in terms of food security, production and diversity, which need to be considered in planning interventions.