Sowing in the sky

By Meenakshi Singh

The year was 1999-2000, Dr. Despommier was giving a class on medical ecology. He asked his students to design rooftop gardens in Manhattan that could feed its entire population. But the calculations showed that available area would not be sufficient to grow enough food. The resultant idea was of farming or growing food inside the buildings which are multistoreyed, hence providing more farming area on a given piece of land. Vertical farming, as Despommier called it, has since been a term talked about a lot. It is claimed to be the next big thing in the field of farming after green revolution.

Vertical farms are build inside multi-floor buildings in urban areas. A typical facility looks like rows of green leafy vegetables grown in a medium of nutrient rich mist. Anchorage is provided by cloth, which is mostly reusable. The primary methods used for facilitating growth are: (i) Aeroponics, the process in which nutrient is provided by air (mist), and (ii) Hydroponics,  which uses water as the medium to provide necessary minerals and nutrients to the growing plants. Vertical farming uses up to 95% lesser water, 50% less fertilizers and zero pesticides, herbicides and fungicides. It works on closed loop agriculture technology, recycling the water and nutrients. Despommier claims that indoor farming is over 90% more efficient at producing food crops, compared to outdoor farming that gives 50% success rate at best (due to pests, diseases and climate conditions).

A hydroponic vertical farm in Minnesota
Credits: Bright Agrotech (CC-SA 4.0)

Essentially, vertical farming is considered good because, it is very efficient and reliable, not affected by climatic adversities (such as drought or floods), and reduces transport cost. Most importantly, it increases the self-dependence of the cities, making them more sustainable. Additionally, it helps in combating with climate change by decreasing global greenhouse gas (GHGs) emissions and increasing forest areas (which are cleared for farmland).

Stan Cox, who is a senior scientist in The Land Institute in Salina, Kansas, US, on the other hand, thinks that vertical farming is a fantasy with a lot of unanswered questions. He disapproves an essential claim made by vertical farming supporters that we would be short of cropland to feed the population, which is expected to reach 10 billion by 2050, about 80% of which will live in urban centres. (Though, as a later clause to his ‘we have ample land’ argument, he adds that ‘we just need to stop abusing the soil we have’.) Critics also say that the amount of energy required to grow the crops indoors would very much outweigh the benefits from cutting costs of shipping. The cost of initializing vertical farms, to prepare the infrastructure and technology would be so high, that the produce would be only eligible for people with high disposable income. People from real estate also question allotment of land for farming in urban areas, where there’s already space crunch, and more appropriate uses of land exist. Vertical farming has also not been efficient till now in producing grains and just indulges in growing vegetables which constitute a very small fraction of one’s diet.

However, even with these ‘defects’ or ‘unanswered questions’, vertical farming is picking pace. Various universities and institutions have built these farms and supply their organic products to local consumers. Though many question its ‘organic’ nature stating the lack of soil or sunlight during production, people who consume the vertical farm produce claim that it tastes ‘good-spicy and overwhelmingly flavorful’. Green Sense Farms, in Indiana, has collaborated with Phillips Lighting, to devise most efficient lighting conditions/technology for indoor farming. Proponents of vertical farming are hopeful and assert that with collection of more data and experiences, the process and the technology associated with vertical farming will definitely improve, as happens with every project.

Despommier explains that it is not only the question of feeding urban population, vertical farming also assists in undoing some of the damage done to ecosystems because of farming. He does not demonize agriculture the way Jared Diamond does, but maintains that farming causes pressure on forests, grasslands, and ‘wastelands’ and ends up disturbing ecosystems. Although, to completely revolutionize the farming system would not make sense. Despommier also says, cities should work towards becoming eco-cities and create sustainable ecosystems, of which primary productivity is an essential quality. He asks the world to ‘generate just 10% of our farm production within the cities’, not just to validate, but also to learn more about vertical farming and fight out of climate change by using it.

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