Greening of Daycare Yards with Biodiverse Materials Affords Well-Being, Play and Environmental Relationships.

Nature contacts are recognized as positively contributing to humans' health and well-being. Although there have been projects to green daycare or schoolyards, yard greening and microbial biodiversity have never been studied simultaneously. We asked whether simultaneously increasing biodiversity exposure and greening urban daycare yards affects 3-5 years-old children's physical activity and play, their environmental relationships, and their perceived well-being.