Dutch nature organisations developed the Green Traineeship, combining out-of-the-classroom learning with voluntary work in nature for young adults, with the aim of supporting them to towards future action for nature. To better understand how young adults' engagement with nature can be strengthened and facilitated, we studied perceived knowledge and competences of participants of the Green Traineeship, including their motivations, their connectedness with nature before and after the experience of the traineeship through surveys. We found that trainees primarily wanted to learn, find a way to turn their green intentions into actions, and find a community of professionals and like-minded peers. Their connectedness with nature was quite high at the start and remained stable during the programme. Fulfilling the trainees' basic psychological needs (autonomy, competence and relatedness) were trainees led to more willingness to act for nature and a clearer idea of the possible paths to do so. Combining volunteering (autonomy through meaningful contributions), learning (competence), and creating a community (relatedness) shows promise in facilitating young adults to find pathways towards green actions.