Residential gardeners’ nature connection and garden characteristics determine the ecological benefits of pro-pollinator interventions

Abstract Residential gardens can provide pollinator habitat and thus contribute to mitigating declines of insect pollinators. To further improve gardens for pollinators, it is necessary to understand the factors and pathways leading to successful conservation interventions. We studied how the success of two common pro-pollinator interventions, garden meadows and flower plantings, were influenced by gardeners’ degree of nature connection, pollinator knowledge, gardening skills, demographic factors, characteristics of the garden, and the surrounding degree of urbanisation. We collected data through a citizen science campaign using an online questionnaire and used Structural Equation Modelling to assess the pathways determining the ecological success of interventions, i.e., the level of pollinator activity. Gardeners’ degree of experiential nature connection and internalised identification with nature, and their age, largely drove the success of interventions through associations with knowledge of pollinators and gardening, and garden characteristics. Higher pollinator activity was reported from gardens with fruit and vegetable cropping, indicating habitat complementation between flower plantings and garden crops. Larger and older interventions generally contained higher species richness of flowering plants and higher pollinator activity. The two interventions differed slightly in the drivers found: The strongest drivers of flower planting success were knowledge of gardening, economic expenditures related to gardening, and gardener’s age, while meadow success was additionally driven by education level and the wildness of the garden. The level of urbanisation had a direct negative effect on pollinator activity only for meadows. To optimise benefits to pollinators, plantings kept over many years should be prioritised in densely urban areas, while species-rich garden meadows are particularly valuable in rural and suburban contexts. Increasing the public’s attachment to, and knowledge about, nature may further improve gardens for pollinators. Gardening could constitute an arena for such activities.