The past decade has seen a greater emergence of green roofs and vertical gardens created by artists, designers, architects and urban gardeners to combat the lack of flora in the city than ever before.

Buildings around the world — from the Musée du Quai Branly in Paris (shown) to the Queens Botanical Garden in New York — have embraced green walls or roofs for all their economical, environmental, and aesthetic values.

Vertical farms and gardens are also being envisioned as new ways to feed local and organic foods to city dwellers. Largely based on the principles of hydroponics, the logic goes that vertical gardens would also be mostly self-sustaining, because they would capture large amounts of natural sunlight and water, and could use wind as an energy source.

These and other urban parks and gardens have many potential uses beside promoting energy-efficiency. They could provide locations for a city farm or community land-trust; an outlet through which hundreds of people can learn about farming and agriculture; and the addition of much needed plant and animal life to the otherwise concrete jungle. 

A project of SEA (Social Environmental Aesthetics), and conceived by Papo Colo, Vertical Gardens is an exhibition of architectural models, renderings, drawings, photographs and ephemera that depict or imagine a vertical farm, urban garden or green roof. It features over 20 projects, both imaginary and real, by artists and architects that envision solutions for building greener urban environments. The exhibit runs till May 23 at 475 Tenth Ave in New York City.