Many foodies pin the blame for farming’s ills on “unnatural” industrial agriculture. Agribusinesses create monocultures that destroy habitat and eliminate historic varieties. Farmers douse their crops with fertiliser and insecticide, which poison streams and rivers—and possibly human beings. Intensive farms soak up scarce water and fly their produce around the world in aeroplanes that spew out carbon dioxide. The answer, foodies say, is to go back to a better, gentler age, when farmers worked with nature and did not try to dominate it.
However, for those who fancy some purple-ruffles basil and mizuna with their lamb’s leaf lettuce, there is an alternative to nostalgia. And it involves more intensive agriculture, not less.
A vast selection of fresh salads, vegetables and fruit is on the way, courtesy of a technology called vertical farming. Instead of growing crops in a field or a greenhouse, a vertical farm creates an artificial indoor environment in which crops are cultivated on trays stacked on top of each other. From inside shipping containers in Brooklyn, New York, to a disused air-raid shelter under London’s streets and an innocuous warehouse on a Dubai industrial estate, vertical farms are sprouting up in all sorts of places, nourished by investment in the business from the likes of Japan’s SoftBank and Amazon’s founder, Jeff Bezos.
This should cheer anyone who wants organic produce that has been grown without pesticides and other chemicals, and which has not been driven hundreds of miles in refrigerated lorries or flown thousands of miles in the belly of a plane. Such farms can greatly reduce the space needed for cultivation, which is useful in urban areas where land is in short supply and expensive. Inside, climatic conditions are carefully controlled with hydroponic systems supplying all the nutrients a plant needs to grow and recycling all but 5% of their water—which is incorporated in the crop itself. Specially tuned led lighting generates only the wavelengths that the plants require to prosper, saving energy. Bugs are kept out, so pesticides are not needed. Foliage and fruit can be turned out in immaculate condition. And the harvests last all year round.
There is more. As they will remain safe and snug inside a vertical farm, long-forgotten varieties of fruit and vegetables can stage a comeback. Most of these old-timers have been passed over by varieties bred to withstand the rigours of intensive farming systems. A cornucopia of unfamiliar shapes, colours and flavours could arrive on the dinner table.
This glimpse of Eden is still some way off. The electricity bill remains high, principally because of the cost of powering the huge number of leds required to simulate sunlight. That means vertical farming can, for the time being, be profitable only for high-value, perishable produce, such as salad leaves and fancy herbs. But research is set to bring the bill down and the costs of renewable energy are falling, too. In a hot climate such as Dubai’s extensive solar power could make vertical farms a valuable food resource, particularly where water is scarce. In a cold climate thermal, wind or hydroelectric power could play a similar role.
Some field crops, including staples such as rice and wheat, are unlikely ever to be suitable for growing in vast stacks. But as its costs fall thanks to further research, vertical farming will compete more keenly with old-fashioned greenhouses and conventional, horizontal farms where crops grow in the earth. As an extra form of food production, vertical farming deserves to be welcomed, especially by the people whose impulse is to turn their back on the future. ■
Source: The Economist