Singapore

At a local FairPrice Supermarket in central Singapore, you'll find baby carrots grown in Bakersfield, Calif. — the same ones for sale at my local grocery store in Washington, D.C. Such well-traveled vegetables aren't unusual in the tiny island state, which imports more than 90 percent of its food from some 35 countries. Singapore may be one of the most affluent countries in the world, but it depends heavily on others for basic foodstuffs. A new crop of farmers is trying to change that. Just as property developers build up when they can't build out, so, too, are these agricultural pioneers. Vertical farming is taking hold across Singapore — not only in greenhouses in the vanishing countryside but also on rooftops in the heart of the city, amid soaring skyscrapers and housing blocks.