Eco Wise

For the Future of Farming, Look Up

Sunday, August 12, 2007

If you're a follower of eco-chatter, you've probably heard that you should eat locally: The closer the farm, the less fossil fuel required to transport food to your plate. But sticking to a regional diet can be tricky, especially for city dwellers. Farmers markets are a great option but not always convenient. What if you could eat tomatoes and corn that were grown just a Metro stop from home? The idea may sound far-fetched, but it might not be far away.

The "vertical farm" or "sky farm" -- a glass skyscraper that functions as a giant urban greenhouse -- is an idea gaining traction among environmentalists and venture capitalists. Championed by Dickson Despommier, a professor of environmental health sciences at Columbia University, the concept calls for tall buildings in which each floor would host hydroponically grown crops, including grains, as well as small livestock such as pigs.

Computers would monitor the lighting and watering, and everything would be cultivated without pesticides. Vertical farms would generate their own energy through wind power and clean-burning plant waste, purify urban sewage to use for irrigation, and collect and reuse evaporated water.

Nothing has been commissioned yet, but architects have designed a number of prototypes, including buildings tailored to New York and Toronto. (To see the designs, visit the Vertical Farm Project at The plans call for green building technology that's already in use, but there are still hurdles: the complicated integration of cutting-edge agricultural and architectural concepts, and, of course, the cost of building them.

Still, vertical farms might be an important step to preserving the planet. "With arable land decreasing at an alarming rate due to erosion, nutrient depletion, droughts, floods, etc., vertical farming in urban centers seems like a viable option that needs to be tried," Despommier writes in an e-mail.

The global population is expected to balloon by 3 billion in the next 50 years, according to the U.S. Census Bureau. Feeding those people would require more farmland than is available. Plus, new farms are often formed by destroying forests, which are carbon-absorbing, planet-cooling powerhouses. Allowing large swaths of farmland to return to being forests -- a process that takes decades -- could eventually sop up massive amounts of carbon dioxide, helping stabilize the global climate.

Depending on its size, each vertical farm is estimated to be able to feed from 10,000 to 35,000 people annually -- a significant sum, given that more than 80 percent of the developed world's population will live in cities by 2050, according to the Population Resource Center.

Though you won't be able to buy blueberries grown on the Blue Line anytime soon, you can do your best to support the vertical farm's principles. Cultivate your own herbs in window boxes. If you have a back yard, plant a vegetable garden; if you don't, join an urban garden. And when shopping or dining out, find out where the food comes from and choose wisely. Remember: There's no place like home.

-- Eviana Hartman

© 2007 The Washington Post Company