Innovation is essential for agricultural and economic development, especially in today’s rapidly changing global environment. While farmers have been recognised as one of the key sources of innovation, many studies on agricultural innovations continue to consider farmers as adopters of externally-driven innovations only. Based on cross-sectional data from 409 farm households, this study, in contrast, analyses the innovation-generating behaviour among rural farmers in northern Ghana. Inspired by two innovation theories – induced innovation and innovation systems – we focus on the determinants of innovation behaviour. Employing recursive bivariate probit and endogenous treatment-regression models which control for selection bias, we find that participation in Farmer Field Fora, a participatory extension approach with elements of the innovation systems perspective, is a key determinant of innovation behaviour in farm households. Other important determinants are education, climate shocks and risk preferences. These results are robust to alternative specifications and estimation techniques. We conclude that policies for the generation of innovations among farmers should focus on education, and on building innovation capacity through institutional arrangements that permit interactions and learning between stakeholders.