There is increasing concern about children's mental well-being and an urgent need for research into how to support positive mental health; including as part of the United Nations Sustainable Development Goals (SDGs). Alongside this is the heightened awareness about diminished access to green spaces and diminished exposure to the arts for children. Our research aims to show the potential for addressing these three issues in tandem through a qualitative case study exploring the work of one charity, Cambridge Curiosity and Imagination (CCI). The charity undertakes arts-based projects in nature with children. In particular, this article considers the implications of CCI artist pedagogues' perceptions of their nature-based practice for children's well-being. The research comprised a 'talk and draw' focus group followed by individual interviews with CCI artists. Findings show artist pedagogues' work has the potential to support aspects of children's well-being through promotion of agency, developing confidence and providing inspiration to support creativity.