Urban ag can adequately contribute to the food system in cities. Cities that keep growing and that are under the constant pressure of climate change, environmental challenges, and social disruptions. Feeding cities is a big thing. Let’s have a look at some successful practices in urban farming.
Urban farming is not a new gig. Its origins can be traced back to ancient civilizations, which used communal gardens to feed their populations. Well-known examples of the practice are cities such as Babylon and Rome, and it continued throughout the Middle Ages. In pre-industrial Europe, many towns had large communal allotments or horticultural plots, where people grew vegetables to supplement their diets. Often, cities were surrounded by commons, community land that was not owned by anyone and where everyone was allowed to pasture their cattle.
An urban ag landscape
Today, circumstances are often more challenging because of larger populations and less available land, but thanks to modern technology and innovation, practices in urban farming are becoming more promising than ever. With advances such as vertical farming and hydroponic systems, people in cities can now grow food more efficiently while using less space and resources. In many places, high tech now joins the more traditional ways of farming.
Even meat is on the radar. Not by raising livestock, which is hard to combine in urban areas because of the substantial need for space, and for hygienic and health hazard issues. But new and promising technologies like cultivating meat from cell tissue may one day be as normal as growing lettuce on a hydroculture. Now still practiced in labs, soon maybe done even in the basement of a supermarket….
On the other hand, community and rooftop gardens should not be ruled out yet. Although not high-tech, and with more modest yields, they offer a wider scope of benefits, both in agriculture and in social value.
Popular practices in urban farming
How can you grow food in cities? Patches of available land are scarce, limited in size, and scattered all over the place. Sometimes they are polluted and can’t be used for growing food crops. Other locations offer space, but no soil, like industrial structures. For all of them, however, proven methods for growing food are present and amply exploited.
Hydroponics is a way of growing plants without soil. Instead, plants grow in water that has special nutrients added to it. Hydroponic farming is a great way to adapt to tight spaces, as the setup can be adjusted according to how much space you have. The plants are suspended in the nutrient solution, and their roots get an even supply of oxygen and nutrients. This helps them grow faster than they would in soil.
Aeroponics is a type of hydroponic system that sprays roots with nutrients in the form of mist instead of submerging them in water.
Aquaponics is another popular urban farming technology that combines the methods of hydroponics with aquaculture (raising fish). In a closed loop, plants grow on the excrement of the fish. This combination enables farmers to simultaneously produce both plants and fish while using far less water than traditional agriculture methods.
Vertical farming utilizes technologies such as hydroponics and aquaponics to grow plants in vertically oriented, stacked layers. This efficient practice in urban farming requires little space and can be implemented in any urban environment, but is especially suited for warehouses or other industrial facilities.
Growing on substrate
Growing vegetables on a substrate is an alternative growing method used increasingly in urban farming. It utilizes materials such as peat, coconut coir, or rock wool in place of soil. This substrate is typically composed of organic matter, which provides a medium to hold the roots of plants and absorb moisture and nutrients from the nutrient solution circulating around them. The substrate is much lighter than soil, which makes it typically suited for use on rooftops, or in multi-floored buildings.
The benefits of these alternatives are that they eliminate weeds; require less water; reduce fertilizer runoff; increase yields per acre; and help conserve land by producing more food in a smaller area than traditional farming would allow. Additionally, some of these methods can also be used indoors or in limited outdoor space such as patios and balconies.
Another advantage of substrate growing is the absence of fungi and pests that usually threaten soil-grown crops.
It may be somewhat unexpected, but it is possible to practice permaculture in cities too. Permaculture is a method of sustainable living that focuses on creating connections between people, plants, animals, and the environment. This type of sustainable living can be applied to any size space, including urban environments. In urban areas, permaculture is one of the practices in urban farming that utilize existing resources and infrastructure as much as possible, while incorporating natural elements such as native plants and compost. While it requires natural soil, urban food forests can be designed as permacultures, and urban beekeeping projects and utilizing greywater systems are great combinations.
Permaculture is an approach to land management and settlement design that adopts arrangements observed in flourishing natural ecosystems. It includes a set of design principles derived using whole-systems thinking. It applies these principles in fields such as regenerative agriculture, town planning, rewilding, and community resilience.
Urban farms come in many shapes
There are many ways to organize an urban farm and lots of places you can use for it. Let’s mention some of the most popular ones.
Community agriculture in cities is a growing trend that promotes the development of local food systems. It brings people together to create gardens and urban farms in their neighborhoods, utilizing vacant lots and other public spaces. Community agriculture allows for individuals and communities to become more engaged with their local food production and gain access to fresh, healthy produce.
One of the most successful recent examples of urban agriculture is Detroit, Michigan. The city has seen a revitalization of its food system in the past decade due to a focus on community gardening and urban farming. Through this, Detroit has been able to increase access to fresh produce for its residents, as well as create job opportunities and improve air quality by reducing greenhouse gas emissions.
Rooftop gardening is another form of community gardening. This innovative method of cultivating plants and vegetables allows for people to enjoy the benefits of green spaces in even the most densely populated cities. By utilizing containers, pots and raised beds, a single rooftop can become a thriving garden that produces a variety of fresh produce and herbs.
Vertical farming uses walls and vertical structures to make optimal use of available space. Often it utilizes some form of hydroculture to grow plants or crops, and it can be applied both indoors and outdoors.
Greenhouses are used in many places, on the ground or on rooftops. They are an iconic symbol of small-scale farming but are also used in many places for industrial-size production. Their major advantages are to prolong the growing season and to protect crops from bad weather conditions.
In some places, you can find rooftop gardens and rooftop greenhouses on top of local supermarkets, that grow part of the products they sell. This recent development is a very efficient way to produce as close to the market as possible.
Indoors or outdoors?
Greenhouses make a bridge between outdoor and indoor farming. But the differences between them are distinct. Where greenhouses offer some protection from the elements, they make optimal use of light, also to produce warmth.
While indoor farming is completely isolated from weather conditions, light, heat, and irrigation all have to be provided by additional systems. Those come at a price, but the advantage is that indoor production can go on all year and in every season, under fully controlled conditions.
Crops to grow indoors vary from tomatoes, lettuces, and herbs to bean sprouts and berries. Mushrooms and even insects and worms are easy to grow as well.
Depending on the crops, indoor farming usually requires specialized lighting in order to successfully grow plants and vegetables. The most sustainable type of lighting used for indoor farming is LED. LED lighting systems are energy-efficient and long-lasting. Some systems can provide precise levels and specters of light throughout the growing process, and allow plants to grow 24 hours a day, shortening the time from seed to harvest considerably.
This overview presented to you the major practices in urban farming. In the next article in this series, we will look at who is farming the city: enablers and participators and the role they play in urban farming. Want to find out how? Read on!