The aim of this study is to determine the contribution of student interventions to urban greening processes. In two Dutch cities action research was conducted, including reflexive interviews a year after the first intervention, to assess factors causing change in the socio-ecological system. Results show that students and network actors were mutually learning, causing the empowerment of actors in that network by adding contextualized knowledge, enlarging the social network, expanding the amount of interactions in the socio-ecological system and speeding up the process. Students brought unique qualities to the process: time, access to stakeholders who tend to distrust the municipality and a certain open-mindedness. Their mere presence made a difference and started a process of change. However, university staff needed to keep the focus on long-term effects and empowerment, because students did not oversee that. After a year, many new green elements had been developed or were in the planning phase. In Enschede, the municipality district managers were part of the learning network, which made it easier to cause changes in the main ecological network. In Haarlem however, no change took place in the main ecological network managed by the municipality, because no political empowerment of the civil society group had developed yet.