Stakeholder networks underpinning the transformative practice of urban roadside verge greening

• Diverse sectors and stakeholders were connected and contributed to urban verge greening and management. • Information flows comprised almost 80% of the network resource flows. • Local government authorities, a water utility program and peak bodies were key knowledge brokers. • Network communities had distinct functions and composition that transcended traditional silos. • Social network analysis can aid in understanding the adoption of marginal urban greening or sustainability actions. Understanding how social networks facilitate the adoption of marginal urban greening actions can provide valuable impetus to guide transformative change in urban landscapes, which are under multiple social and environmental stressors globally. Social network mapping of resource flows, particularly information sharing, is one tool for understanding the emergent and transformative urban greening practice of landscaping roadside verges with native and/or waterwise plants. Urban roadside greening in Perth, Western Australia, while formerly prohibited, is now increasingly accepted and advocated for by multiple sectors, as a nature-based solution that provides multiple ecosystem services and social-ecological benefits. This study drew on participatory stakeholder mapping to examine the stakeholder network of non-residential actors connected with verge greening. Using social network analysis, we found almost 80% of resource flows across a large network of diverse stakeholders were information related. We identified top providers, recipients, brokers, as local and state governments and peak bodies, and, to a lesser extent, key individuals, community groups, nurseries, residents and environmental consultants and developers. The network was characterized by four dominant and five smaller communities, which we classified into a typology based on composition, structure (quantitative material), and contextual knowledge, including function, dominant roles and responsibilities (qualitative material). These were the ‘planning and development hub’, ‘governance enablers’, ‘water efficient hub’, ‘greenspace hub’. The five smaller communities were ‘advocates’, ‘transformers’, ‘new vision’, ‘local networks’ and ‘early adopters’. The network analysis provides evidence of communities that transcend traditional sector or actor silos, commonly converging around local governments as key knowledge brokers.