Modern populations face high levels of mental health challenges, chronic diseases, and premature death due to preventable conditions. Advances in theory and methods suggest that optimal solutions to these problems will be multifaceted, targeting multiple behaviors and ways of thinking simultaneously. One promising, widely-used approach addressing modern health problems at multiple levels involves community gardens. Utilized in the United States since the 1890s, community gardens are thought to promote community cohesion, mental wellness, and physical health. Do these programs work? If so, what is it about community gardening that promotes thriving? This project addressed these questions using a controlled experimental design, with extensive valid assessment. Participants were randomly assigned to one of five health interventions: community gardening, physical activity, social film club, exposure to nature, or growing a living thing. Each comparison group was designed to rule out or isolate an element of community gardening that may be a cause of observed correlations with good health. After completing a pretest and attending a workshop, participants engaged in their health behavior two hours a week for four weeks. They then completed a posttest. Participants also completed a subset of measures during the intervention period and three weeks after the conclusion of the intervention. Results showed that, regardless of experimental condition, participants improved in emotional well-being, conscientiousness, social relationships, environmental identity, and self-reported health from pre- to posttest. Though the omnibus ANOVA suggested differential group change in environmental identity (such that the garden and nature groups increased compared with other groups), follow-up analyses did not reach statistical significance. There were no changes in sleepiness, physical activity, or produce consumption. Though results were equivocal, this study is the first true experiment attempting to tease apart the causal mechanisms of community gardening in relation to health and wellness. Thus, this dissertation provides a framework—with measures and models—for researchers studying the effects of community gardening and similar broad health interventions. Rigorous research on whether and why community gardening promotes health is still in its budding stages, and continued research attention is warranted considering the potential implications for individual and community health
