Cleaning up abandoned lots and creating community gardens doesn’t just make a neighborhood feel safer—a growing body of evidence shows they really become safer.

Darnell Ishmel’s street in Flint, Michigan, used to be lined with waist-high grass on vacant lots. The blight felt overwhelming, “to the point where I [didn’t] even want to walk outside,” he says. “The dogs are roaming just beyond the corner—you can’t even drive at certain intersections because you can’t see beyond the tall grass at the oncoming traffic.”

That was about a decade ago, when Flint was known for its high rate of violent crime, before the city’s water crisis hit in 2014. In 2012, according to FBI data, 2,774 violent crimes were reported to the Flint Police Department. In 2022, 985 were reported.

Like other “legacy cities” that have experienced significant economic decline and population loss, Flint is still struggling. But now, through the Genesee County Land Bank’s Clean & Green program, Ishmel and hundreds of other residents have been mowing vacant lots. Greening projects like these maintain abandoned spaces, either by mowing them or converting them into gardens and parks. “When we take care of our neighborhood, there’s something about that removal of the blight—it just makes us feel a little bit better,” Ishmel says.

But these projects don’t just make the neighborhood feel safer.

Researchers who have been studying the effects of greening in Flint; Philadelphia; Youngstown, Ohio; and other legacy cities have shown repeatedly that it actually reduces violent crime.

“It is one of the most consistent findings I’ve ever had in my 34-year career of doing research,” says  Marc A. Zimmerman, professor at the University of Michigan School of Public Health.

Dr. Marc Zimmerman speaks with National Geographic about the impact of community greening on violence and crime.