Urban farming has been on a steady increase for many years now as space for agriculture creeps closer to cities and consumers look to reconnect with what they eat. As well as appealing to the health and environmentally conscious market, these systems often seek to achieve community benefits; providing opportunities and education for disadvantaged and minority groups. The size and purpose of urban agricultural systems can range enormously, encompassing: allotments, vertical farming, agroparks and community gardens, ranging from subsistence to industrial sized operations.
“Urban and peri-urban agriculture (UPA) can be defined as the growing of plants and the raising of animals within and around cities” FAO 2018
The main focus of urban agriculture is on the utilisation of underutilised spaces, including rooftops, walls and basements. CloudGro supplies lightweight modules designed to sit atop supermarkets, growing fresh produce on otherwise wasted space, which can then be monitored autonomously and brought down to shop level, creating a farmer’s-market style buying area. The system operates using the waste heat and CO2 generated by large superstores, helping to monetise waste products. The main advantage of inner city or supermarket based farming such as this is the reduction in transportation; saving time, emissions and extra packaging. Costs are reduced through the lack of need for refrigeration and transport, making fresh food more affordable for poorer consumers.
For the highest efficiency, in terms of space required for produce generated, controlled environment systems generate the greatest returns as they can be carefully calibrated to deliver optimum growing conditions for maximum yield. Vertical farming also allows farmers to increase efficiency by growing produce in stacked shelves or vertical planters. The kit used in controlled environment systems and vertical farming can range in complexity from simple roof-top set ups to highly optimised operations where even the wavelengths of light the plants are exposed to is monitored.
Hydroponics cultivates plants in water as opposed to soil, making it easier to maintain a constant supply of nutrition to the plants roots.
Aquaponics adds a second element to the hydroponic system by sourcing the crops nutritional supply from waste water generated by aquaculture; the waste is fed to a system of nitrifying bacteria which convert it into organic nitrogen for uptake by the crop roots. The now filtered water is then safe to return to the aquaculture container. This system makes more economical use of water in return for the production of two outputs; fish and vegetables, whilst creating a more efficient chain of nutrient usage.
Aeroponics involves the suspension of plant roots in a nutrient dense mist. This approach is touted to be even more efficient than hydroponics due to the higher oxygen availability for the crop roots.
For subsistence farming, these systems can be relatively simplified and require minimal inputs, providing a much needed nutritional enhancement and food security for the urban-poor. At the other end of the spectrum commercial operations are focussed largely on high value crops such as herbs and salad greens whose appeal is dependent on retaining freshness but are liable to transport spoilage.
Of course there are also disadvantages to urban farming’s swift rise; A lot of urban agriculture is unregulated and can occur on communal land, creating health risks from improper management of inputs. For the more high tech operations there is still some serious debate over whether the reduction in energy logically inferred through a reduction in transport distance does actually translate into a significant saving.
The expansion of urban areas means these forms of farming are likely to continue their increase in popularity across both the developed and developing world. As growth techniques become more refined, underutilised spaces may well become more productive than traditional agriculture for some leafy crops. With more commercial projects beginning to gain ground it is possible that in the next few years the salad you eat may never have touched soil or even seen the sun. You may even have grown it in your own basement.
Find out more about urban agriculture projects here: