The SolACE project includes a work package focused on on-farm experimentation with trials occurring on farms in seven different farmer networks to test agricultural innova- tions aiming to improve nutrient-use and water-use efficiency. This paper discusses the challenges and successes of the multi-actor farmer-participatory approach employed through this project. Overall, though farmer engagement was generally strong across the project, the de- centralised management of farmer networks through in-country network leads had strengths and weaknesses. Existing networks with established relationships between researchers and farmers provided earlier and regular contributions, while recruitment was much slower in some countries. Trade-offs between scientific rigour and on-farm practicalities affected farmer selection of trial innovations, though farmers were able to benefit from trying new products and technologies in a research-supported setting.