Vertical Urban Farming? Pull Your Head from the Clouds

Dickson D. Desposmmier, in a recent op-ed in the New York Times, argues that the world, faced with increasing billions of mouths to feed, will soon run out of land. According to Mr. Despommier, “the traditional soil-based farming model developed over the last 12,000 years will no longer be a sustainable option.”

Despommier’s answer to this ‘problem’: “move most farming into cities, and grow crops in tall, specially constructed buildings.” Such vertical farms, argues Despommier, would “revolutionize and improve urban life,” while also addressing issues such as agricultural runoff, air pollution, and carbon emissions.

To sophisticated urbanites with little or no exposure to agriculture, vertical farming may seem to present a sort of utopian panacea. But first one must look at the underlying problem Mr. Despommier claims to address: land shortages.

In this case, Despommier fails to show that land shortages will be a debilitating issue, rather than a manageable challenge. Desposmmier presents figures from the UN showing that the amount of arable land per person has dropped from one acre per person in 1970 to about half an acre in 2000, and may drop toward a third of an acre per person by 2050. This simply means that future generations will have less land available per person. But, does this necessarily translate into impending, persistent, worldwide food shortages?

Even prior to the time of Thomas Malthus, there have been voices warning of disaster lying just around the bend with regards to food production and consumption. Yet, over the past two centuries, those tilling the soil (full disclosure: the author comes from a long line of family farmers, and has, from time to time, taken part in some ‘soil tilling’ of his own) have continued to keep pace with ever-increasing demands for food. True, the equitable distribution of this increased productivity sometimes leaves something to be desired (often for reasons of politics, not of production), but one cannot dispute the fact that farmers worldwide have made massive leaps and bounds in productivity.

In the face of less acreage per human, the UN’s Food and Agriculture Organization continues to track increasing output per capita, and projections for the future show production levels able to meet increasing demand. One notable Dutch study showed the world’s farmers, using existing land resources, capable of feeding up to 10 billion people at least a “moderate diet,” if not an affluent one. Such projections have been supported by a “sizable literature,” some of which argues that future production of food will not be an overwhelming challenge, even at populations up to 12 billion. Between 1960 and 2000, the world’s farmers were able to increase food produced per capita, while the world’s population nearly doubled. We have now reached a point where Americans throw away around 14% of the food they buy.

Making better use of the food we already produce, including gleaning of wasted food, and shifting land away from production of non-food crops, would be common-sense steps towards combating current and future food insecurity. Making better, more efficient use of our existing arable land makes more sense, both now, and in the future.

High-rise urban farming, however, is not the solution. Even if we assume that the world will, as Despommier fears, face potential shortages of arable land in the future, the solution he proposes is far from the most feasible initial solution. In his piece, Mr. Despommier states that a prototype farm, covering one eighth of a city block and consisting of 5 stories, would cost around 20 to 30 million dollars to construct. A vertical farm of such size might mean around five acres of indoor production space (city blocks vary in size from place to place). Despommier states that one indoor acre might be able to replace 20 acres of outdoor farmland. So, giving the benefit of the doubt on cost to Despommier, for 20 million dollars his vertical farm might be able to match 100 acres of outdoor production: a cost per acre of around 200,000 dollars.

For that same 20 million dollars, Despommier could purchase nearly 7,500 acres of productive, existing farmland in a state such as Minnesota or North Dakota, (the national average cost for an acre of farmland is about $2,600) and farm it with the latest in sustainable, organic, and/or low or no-till methods, already being implemented by many American farmers. Such practices can minimize or eliminate chemical use, reduce fossil fuel use, and help prevent erosion of valuable soil. In order to match his indoor production, financed at massive cost, Despommier would only need to find a way to increase the outdoor output by very small percentages, using land that is far less costly and readily available. As an added benefit, he’d have the opportunity to protect and preserve the very land he sees as under threat.

Potentially more valuable still would be aiding farmers worldwide in the use of the most modern, sustainable, and environmentally-friendly practices in areas facing severe underutilization and degradation of valuable arable land resources. Since 1961 farmers in Asia have been able to increase their output by nearly threefold, while yields per acre in Africa have remained stagnant. Investing more resources in agricultural extension services to educate and empower local farmers in soil conservation, land stewardship and sustainable production techniques would be a common sense step towards addressing such challenges that would not require the construction of expensive towers, and would allow farmers to protect and preserve the world’s existing arable land while battling local food insecurity. In fact, according to one prominent soil scientist, protecting and restoring soil, the “most basic of resources,” offers “the chance not only to fight hunger but also to attack problems like water scarcity and even global warming.”

Unfortunately, investing resources in such plans, using existing, tenable resources, might preclude Mr. Despommier from building a shiny new building in New York City, where “everyone” could see it. The more cynical observer might also point out that it could cut off a potential revenue stream for his new vertical farm business, which he envisions being financed by “venture-capital funds.”

While vertical farms might be an interesting topic for light-hearted discussion, there is a reason we don’t farm intensively in urban areas: the land is too expensive, with costs that rise even higher building towering structures. That said, encouraging use of local agricultural products, even adjacent to or within urban areas, is a laudable goal. This supports the sort of family farmers that serve as good stewards of the land Despommier sees as under threat. Mr. Despommier need look no farther than his employer’s own Columbia University Greenmarket to find a farmer’s market supplying the very sort of agricultural product he extols and desires. Encouraging urban gardening is also a great idea, allowing people to take an active role in providing some of their own food, while making use of potentially underutilized spaces, at much less cost than “building up.”

There are, to be sure, challenges to be faced moving forward: recent commodity price spikes (which have since abated) inflicted increased food insecurity on the world’s poor. However, such populations are the least likely to be able to afford the gleaming towers of Despommier’s dreams. Despommier and those interested in sustainable agriculture, including many farmers, will be better off trying to protect our existing farmland from urban sprawl, and supporting the use of the latest in sustainable agricultural practices worldwide, to better use and protect the farmland we already possess.

On the other hand, promoting wildly expensive, Buckminster Fulleresque “leaps of faith”, while neglecting existing resources, is not the path towards long-term agricultural sustainability. Instead of pouring limited financial resources into building fields in the sky to serve as playthings for the urban elite and venture capitalists, farmers, governments and investors worldwide would be better served by plowing resources into making better, more sustainable use of the land that already exists, for the benefit of all.

Matthew is a Research and Development Analyst for Praxis Strategy Group, and a native of Crary, ND.