The soil has been mixed with human thought and substance. These fields … have moved and walked and talked and loved and suffered; hence one feels kinship to them and at home among them.

~John Burroughs, Fresh Fields

Climate change is expected to knock extreme weather up a notch — droughts will become droughtier, floods will become floodier, and storms will become stormier.

~James Gaines, Upworthy

The guy on the housetop caught my eye. He was mowing, pushing his lawnmower back and forth across the roof.

I was driving just outside Fairbanks through an area with many log cabins. Several had sod roofs, and I guess, in that situation, you mow your roof as well as your lawn. Every time I hear the words “green roof,” I think of that scene.

Of course, today the term green roof usually refers to the gardens planted atop flat-roofed commercial, office and residential buildings. They collect precipitation, help clean up air pollution and offer a haven of serenity in busy urban areas. In a view from our hotel in Vancouver, we could see dozens of roof-top and balcony gardens throughout downtown. It softened the sharp edges of the city and made it feel more inviting.

A similar approach is to plant vegetation on the walls of buildings and urban structures. Buttressed freeways also provide appropriate surfaces and the vegetation helps to mitigate noise as well as pollution. Green walls can also help to moderate surface temperature and reduce temperatures inside buildings. They are more common in other countries, where other vertical surfaces, such a freeway piers, are being used. While the intent of green walls may be aesthetic and they may be expensive to maintain, the environmental and social benefits are as real as for green roofs.

A further concept (old idea, new application) creates vertical farms inside large buildings. Multi-storied glass walls of skyscrapers funnel sunshine onto a wall, where shelves of different heights accommodate different crops. Hydroponics provide moisture and nutrients. Other kinds of buildings may also serve as multistory greenhouses, but may require more artificial light.

The attractions of farming indoors include the environmental and social benefits of outdoor structures; but protection from pests and the vagaries of weather also results in longer growing seasons, multiple harvests, and potentially shorter transportation distances to market. As with any greenhouse operation, additional costs are incurred for pumping and climate control (lighting and heating).

The recent surge in indoor farming of marijuana has created a demand for indoor growing operations and has significantly reduced their costs, making other vertical farms more economical. And other higher-value crops (basil, tomatoes, strawberries, flowers, houseplants) are already economically grown in greenhouses and would shift easily to vertical farms.

One new high rise residence is being designed to use up to twenty-percent of its space for vertical farming and proposes to provide much of the produce for its residents. As more buildings like this include vertical farms, it is hoped the additional growing capacity will ameliorate the need for increased farmland. This could mitigate the destruction of wild natural areas for new agriculture to feed a growing population and possibly allow some farmland to be reclaimed for nature. Less productive farmland would presumably be the first to be abandoned and would be the best returned to pre-agriculture conditions.

Growth in vertical farms could also help reduce the “food miles” that much of our produce now travels from farm to consumer. Reducing this distance will result in fresher, healthier food, fewer global warming emissions and a more sustainable environment. On the other hand, an alternative approach to “food miles,” a life-cycle analysis, challenges some of these supposed benefits. This analysis takes into account the efficiencies of industrial farming and large scale transportation (much of which is subsidized by governments). Although, if vertical farming reduces the environmental costs of plowing, fertilizing, irrigation and transportation, even a life-cycle analysis may show better results.

Another reason to create vertical farms may be the creation of more jobs in urban areas, replacing traditional farming-related jobs in rural areas. While potentially exacerbating rural unemployment created by the dismantling of traditional farms, the vertical farms may provide jobs for farm laborers moving to cities in search of work, consistent with current population shifts from rural areas to urban areas.

It is expected that relatively few existing buildings may be suitable for vertical farming without major modification, but anticipated growth in urban areas offers an opportunity to take advantage of the concept with new structures. As with the expansion of the marijuana industry, the creation of more vertical farms should reduce the costs and other barriers to their implementation. Vertical farming, along with green roofs and green walls, offers hope for urban areas to become more ‘natural,’ more livable and more sustainable.

Now if we could just invent a vertical lawnmower…

Additional information:

100-Story Food Tower is Entrepreneur’s Dream, Jennifer Kaplan, The Denver Post, Feb 6, 2017

Food That Travels Well, James E. McWilliams, The New York Times, August 6, 2007