Three views of the vertical farm

GROWING crops in vertical farms in the heart of cities is said to be a greener way to produce food. The idea is that skyscrapers filled with floor upon floor of orchards and fields, producing crops all year round, will sprout in cities across the world. As well as creating more farmable land out of thin air, this would slash the transport costs and carbon-dioxide emissions associated with moving food over long distances. But the concept is still 

unproven. Does it really stack up? To accompany our article on vertical farming in this week's issue, here are three videos offering different perspectives on the subject.

First, Dickson Despommier, author of "The Vertical Farm" and the progenitor of the concept, explains what a vertical farm might look like and how the eco-cities of the future might work.

Although a true vertical farm has yet to be built, there is much enthusiasm for the idea among architects. We asked four architects to describe their designs for the vertical farms of the future.

In practice, the nearest thing to a vertical farm so far is urban hydroponic farming, often on rooftops. BrightFarm Systems is a company that is vying to run commercial greenhouses on New York's rooftops. We tour their first projects, on a boat and a school.