“What is the impact of gardening on the psychological health of adults? A scoping review.”

Abstract

Recently, there have been concerns that the prevalence of mental disorders has increased significantly, threatening the mental health of a large segment of the population. Therefore, there has been a call to improve the psychological health of the general population using non-pharmacological interventions (e.g., gardening and green spaces). Although several scoping reviews have examined the psychological outcomes of green spaces, there is a lack of scoping reviews that examine the psychological outcomes of gardening. Scoping reviews in this research area can be valuable because they identify potential methodological limitations, informing future research. Further, they can explore the scope of evidence, which can identify unanswered research questions. Therefore, this scoping review aimed to explore the scope of evidence as well as identify the methodological limitations in this research area in order to inform future research. The scoping review was guided by a framework developed by Arksey and O'Malley (2005). Different databases were used to access relevant studies, including Scopus, Medline, and the Web of Science Core Collection (WSCC). The search yielded 26 studies. Gardening can lead to a wide range of psychological outcomes, including a reduced risk of depression, with a higher effectiveness of community gardening in decreasing depression compared to individual/home gardening, a decrease in anxiety, mental resilience and relief from stress, escape, enjoyment, and relaxation, better cognitive performance, a sense of community and social relationships, and a greater sense of meaning of life, although there is a greater effect size in individualistic than collectivist cultures and an overly simplistic approach to the association between gardening and psychological outcomes.

Further, there were several methodological limitations, such as limited use of objective measures (e.g., salivary cortisol levels, fMRI), a lack of use of the Core Outcome Sets (COS), a lack of studies with long-term follow-up, a lack of studies that examined the difference between doing the gardening activity and the mere presence of being at the gardening site, and a lack of studies from different countries (Africa, Asia, and South America). Limited studies examined the impact of mediators and moderators. Further, known facts were usually not taken into account. Researchers are advised to address these methodological gaps, as this will improve the quality of evidence in this emerging research area. Moreover, policymakers are advised to provide the required financial support to urban planners to increase the presence of gardens, as they can encourage local people to engage in gardening activities. Further, initiatives that introduce community gardening in public gardens can be adopted by local governments worldwide. Keywords: gardening, green spaces, psychological health, depression, anxiety, stress