Urban farms are sprouting up in US cities that are not known for agriculture.

Rooftops and warehouses are being used to grow local, sustainably produced food.

Many stores in New York get their produce from the country's west coast, which means a lot of items are already a week old before they hit store shelves in the east.

What was once a community project has become a commercial business but experts caution that the business model is still new.

Al Jazeera's Kristen Saloomey reports from New York.