Agroforestry (AF) is promoted as an environmentally sound farming practice to address the pressing challenges of meeting a rising global demand for agricultural commodities while conserving biodiversity. Although AF played an important role in European farming in the past, reintroducing the planting of trees in fields is a radical innovation in the modern context, and is, initially, a researcher's idea. This paper investigates stakeholders’ perspectives on modern AF in two contrasting sub-regions of southern Belgium (Wallonia). Using Q methodology to identify patterns of subjectivity, we found that the conversation splits into three idealised-types of discourse that reflect different farming styles. Only one of the three discourses is in favour of AF. The results indicate that the paradigm type (holism vs. reductionism) underlying each discourse is a major factor that influences stakeholders’ position on AF. The main barriers hampering mainstreaming of AF seem cognitive in nature, and are related to the level of ecological knowledge. By exploring the ‘cognitive unlocking process’, our Q methodological study led to the identification of two readily available strategies to scale up AF: (1) ecological education and (2) social learning within multi-actor innovation networks. Such networks could foster on-farm innovation development and research, in which the farmer is an expert at the same level as the researcher. While this study focuses on the development of AF, the findings could be extrapolated to other agroecological innovations.