Could urban agriculture feed the cities of the future?

Urban agriculture is increasingly common in cities. This picture shows one of six farms created by the New York City Housing Authority in Brooklyn, New York. Photo: Leticia Barboza/AFP

Vertical farms, rooftop farms and computer-controlled growing environments are an emergent phenomenon in cities around the world, which are eager to take advantage of the many benefits of urban agriculture.

However, the question remains: will urban farms be able to produce enough food to make cities self-sufficient?