About this Episode
Violent crime has fallen in parts of the United States city of Philadelphia after abandoned lots were turned into green spaces. Research found that neighbourhoods near restored plots saw a 29 percent drop in gun violence and a 21 percent fall in burglary. Around 12,000 vacant lots have been cleared, planted and regularly maintained.
Researchers say neglected plots often attract illegal dumping, drug sales and hidden weapons. Cleaning and maintaining these spaces removes places where crime can occur unnoticed. It also signals that residents and local organisations are monitoring the area.
The work is carried out through the LandCare programme run by the Pennsylvania Horticultural Society, a non-profit organisation promoting urban greening. The programme removes trash, cuts vegetation and plants grass on abandoned lots. Studies show that nearby areas recorded lower levels of gun violence and burglary after these interventions.
Research from other regions suggests similar effects. Studies in the United States and Europe have found that neighbourhoods with more vegetation often report lower levels of violence. Researchers at the University of Illinois Urbana-Champaign analysed data from more than 3,000 counties and found that higher vegetation levels were associated with fewer fatal police shootings.
Studies in London found areas with well-maintained parks and street greenery reported fewer violent incidents. Urban projects in Barcelona and Copenhagen also showed that redesigning neglected spaces and adding vegetation increased street activity and informal supervision.
City planners in Europe often combine greenery with improved lighting, open sightlines and spaces for community use. Researchers say the positive effect depends on careful design and ongoing maintenance.
