Drawing on the authors’ personal experience in the Edible Public Space project (Leeds, UK), this paper explores the “spheres of influence” and contradictions that shaped the project’s trajectory. We identify and analyse the dynamics and contradictions at play in the formation of an urban gardening group grown out of a coming together of scholarly and committed action ambitions and aim to capture learning elements for scholarly activism, political gardening and radical urbanism. We explore the action research intervention with a focus on the role of spatial interventions in fostering social innovation in the public food and land agenda. We structure our discussion in a threefold conceptual framework: (i) a discussion on shifting planning arenas and their understanding in social innovation; (ii) an overview of the role of political gardening practices, in particular of food commons/food sovereignty initiatives, in envisioning and implementing alternative urbanism and (iii) a discussion on the action research nexus, through a thick case study description in which we also unpack our own engagement and positionality. Doing so, we aim to contribute to the creation of an active memory of political gardening. The paper will speak in particular to a rising number of researcher–gardeners–environmentalists, and aims to problematise the links between research-informed strategic thinking and actions, and the vocation of critical urban theory to provide and make visible alternatives for social change.