Urban Farming: Should we Grow Food in Cities?
11 minute read
Updated on Mon Dec 14 2020
Why bring agriculture to cities?
However, people living in these areas are almost completely dependent on food brought in from rural farms. They are, therefore, vulnerable to changes in food prices and supply. Access to fresh fruit and vegetables is also often extremely limited.
Food processing, such as canning, drying or freezing, can extend shelf life and reduce food waste. However, this uses energy, and important nutrients and vitamins can be lost or altered in the process.
Do we have space for urban agriculture?
Micro-gardening is one solution. This involves growing fruit, vegetables and herbs in small spaces, such as rooftops, balconies, and patios. Rooftops in particular offer large amounts of flat, sunny space on which to grow plants.
Indeed, if all suitable roof space in Bologna, Italy, was used for urban agriculture, approximately 624 tons of CO₂ could be captured every year, and enough vegetables could be grown to feed over three-quarters of the city!
To ensure a regular water supply, gutters, pipes, and water butts can be used to channel rainwater that would otherwise have been wasted to the plants. Food waste can also be recycled and used as compost to fertilise crops.
However, not everyone has a balcony or patio, and setting up a roof garden can be expensive. While people in cities scramble for every inch of available outdoor space, large areas of indoor space are left abandoned. What if we could grow food in these areas too?
Can farms be set up indoors?
Crops can be stacked in layers so more of them can be grown in a small space. This is called vertical farming. Vertical farms can be set up almost anywhere: in office buildings, underground, in shipping containers, and even in space!
Vertical farms often grow plants in water instead of soil. This system, called hydroponics, allows farmers to ensure plants receive nutrients in exactly the right amounts because nutrient levels in the water can be precisely controlled. No soil also means no weeds or other soil-based pests, reducing the need for pesticides.
So far, we have discussed how crops can be grown in cities. What about meat?
Can we farm animals in cities?
Hydroponic systems can be combined with aquaculture in a circular system that uses fish waste to fertilise crops. This is called aquaponics. Water from the fish tank is transferred to growing plants, which remove nutrients from fish waste. The water is then recycled back to the fish tank.
Aquaponic systems imitate natural nutrient cycles, removing waste while conserving water. Because water is recirculated within a closed loop, these aquaponic systems can be set up almost anywhere, including on top of buildings!
Developments in urban agriculture are changing people’s perceptions of farming and food production as a whole. However, while they have many benefits, farming by these methods alone will not provide enough food to feed our growing population. To ensure that people have sufficient access to food, urban agriculture needs to be combined with traditional farming methods.Next Chapter