Vertical farming and hydroponics are other examples of green technologies that are improving our agriculture in so many ways.
Thanks to this technology is now possible to consistently produce large quantities of quality food, also where the weather or space would not normally allow it.
What is vertical farming?
The concept of vertical farming is the brainchild of Columbia University Professor Dickson Despommier, who developed it in discussion with students he was teaching as part of a course on Medical Ecology. The idea behind it was to grow food ‘vertically’ in disused urban spaces, using a hydroponic or aeroponic (where plant roots are misted rather than submerged) system. Despommier argued that foregoing soil offered a way of mitigating widespread soil degradation, and that vertical farming could provide a local food source within cities, where the space to grow food in soil, on a significant scale, is minimal.
Hydroponics and organic food
There is fierce debate, however, over vertical farming and the hydroponic and aeroponic production systems it overwhelmingly depends on, and it’s an argument that reaches into the heart of how we define ‘sustainability’. Hydroponic growing has been in commercial use since the early 20th century. Plants are grown in water or in an inorganic fabricated substrate, in buildings that may or may not have windows – if not, LED-lighting is used. The biggest criticism it faces is that plants are fed with artificial nutrients, because they don’t have access to the microbiology of healthy soil. This goes against one of the most fundamental early articulations of organic farming principles from Lady Eve Balfour, the leading founder of the UK’s Soil Association, that, “the health of soil, plant, animal and Man is one and indivisible.” For that reason, the UK’s Soil Association has refused to give organic certification to produce not grown in soil, and critics see it as ‘wet’ chemical farming, where chemicals are simply added to water instead of the soil.
The spectrum of sustainability
On a smaller scale, companies like Grow Bristol, whose tagline is ‘Fresh. Local. Sustainable.’ provide one example of the social and agricultural role that vertical farming with hydroponics can play in an urban city centre. Dermot O’Regan, who runs Grow Bristol, has a background in environmental policy. He was interested in providing food year-round to the local community in Bristol. O’Regan was concerned by the heavy water use in agriculture, and, since there wasn’t much soil in downtown Bristol anyway, it made logical sense to buy a shipping container and start a hydroponic farming enterprise inside it. Grow Bristol is set-up as a Community Interest Company with a social mission, and education and engagement is a component of what they do, inviting groups in to visit and offering training opportunities for volunteers and eventually, possibly, jobs to the local community. At the moment they grow micro-greens for a range of restaurants and shops through the city. Like many committed to vertical farming, they see Grow Bristol as a component of the wider food system, one aligned with sustainability, rather than with the environmental degradation of industrial farming.
Vertical farming’s viability
Vertical farming has also struggled with financial viability and this has consequently limited what can be grown this way. The cost of energy can be significant, and some crops are much more expensive than others. Consequently, this system has been primarily used for the production of greens such as kale and spinach, and micro-salads. The energy that goes into producing more substantial vegetables like potatoes and other root vegetables makes these crops prohibitively expensive. Stan Cox of the Land Institute has pointed out in an interview that, “if you got a plant like tomato or sweet corn…that produces a fleshy product, that requires about 1200 kilowatt hours of electricity for lighting to produce one kilogram of food minus the water that’s in the food. That’s about the annual energy consumption of the average American refrigerator for a year, all to produce just two and a quarter pounds of dry matter.” So, in recent years, the narrative around this production method has focused more and more on its role as a part of the wider food system, rather than as a replacement for it.
