Greening vacant urban land significantly reduces feelings of depression and improves overall mental health for the surrounding residents, researchers from the Perelman School of Medicine and the School of Arts & Sciences at the University of Pennsylvania and other institutions show in a new randomized, controlled study published in JAMA Network Open. The findings have implications for cities across the United States, where 15 percent of land is deemed “vacant” and often blighted or filled with trash and overgrown vegetation.
For the first time, the research team measured the mental health of Philadelphia residents before and after nearby vacant lots had been converted into green spaces, as well as residents living near untreated abandoned lots, and those that just received trash clean-up. They found that people living within a quarter of a mile radius of greened lots had a 41.5 percent decrease in feelings of depression compared to those who lived near the lots that had not been cleaned. Those living near green lots also experienced a nearly 63 percent decrease in self-reported poor mental health compared to those living near lots that received no intervention.
The findings add to the growing body of evidence showing how revitalized spaces in blighted urban areas can help improve safety and health, such as reducing crime, violence, and stress levels. The most recent study from the same team in February found up to a 29 percent decrease in gun violence near treated lots. This latest work is believed to be the first experimental study to test changes in the mental health of residents after nearby vacant lots were greened.