Purpose: It remains a critical question how to support farmers to develop towards more sustainable practices. Earlier experiences reveal that on-farm demonstrations (OFDs) can be part of the answer. Therefore, we investigate OFDs as potential transformative learning spaces. Methodology: We apply a mixed methods approach, using an observation tool, participant surveys and telephone interviews. We compare 15 different OFDs, divided into two groups: OFDs with and without facilitated dialogue. We investigated differences based on core inducing processes of transformative learning: disorienting dilemma and (self-)reflection. Additionally we investigated the adoption decision making process half a year after the OFD took place. Findings: Participants in facilitated dialogue OFDs agreed significantly more on experiencing surprise, an indication of disorienting dilemma, and on having reflected and learned. Most mentioned adoption barriers are a lack of relevance for the specific situation and a need for more information. Most mentioned suggestions indicate a request for more real life application. Practical implications: This research indicates that OFDs with facilitated dialogue can trigger more cognitive conflict and reflection processes of attendees, and thus support learning processes on (more) sustainable agricultural practices, as opposed to OFDs without deliberate dialogue facilitation. Theoretical implications: Our study demonstrates that transformative learning theory can inform research on agricultural learning spaces, such as OFDs, on effective triggers to support learning and competencies towards more sustainable agriculture. Originality: Based on rich empirical quantitative and qualitative data we reveal that facilitated dialogue enhances learning during OFDs, but this does not seem to be a common practice.