‘Plant blindness’ stops people from recognizing the important role that plants play in society, and is acute when it comes to seeing how plants support health. The social sciences are beginning to explore how plants are imbricated in sociopolitical processes, including ones that produce health. This paper theorizes people-plant relations and the agency of plants in the production of health, drawing on data from a multispecies ethnography conducted in Toronto’s largest social housing community during the 2018 growing season. The paper applies a posthumanist lens to find that food-producing plants in the area exert their agency and are health-supporting actors when collaborating with residents to advocate for community gardens and influence neighbourhood design. By arguing that plants are actual agents of change in sociopolitical processes, the article deepens an understanding of the health-supporting role of plants and provides empirical evidence for a view of health as a process, as opposed to a status, that is produced through relationships. The paper suggests that the term ‘relational health’ be used to describe a conception of health that recognizes that health is produced through interconnections and interdependencies, including between people and plants. The article contributes to discourses exploring the human health relationship to nature, including One Health.Copyright © 2021 Elsevier Ltd. All rights reserved.