Urban farms are becoming increasingly popular in cities around the world. Creative farming models are now being cultivated in a diverse range of urban spaces, from rooftops to within tall, enclosed buildings. These innovative growing methods prioritize sustainability, which plays a key role in making sure that our urban creations have the least negative impact on the environment. Here are 5 ways to maximize sustainability in your urban farm.
One literally ‘top’ trend in urban agriculture is rooftop farming. This method makes clever use of an urban space that is typically unused and has been praised for its positive environmental impact. Rooftop farms provide extra insulation for buildings, lower temperatures in summer and maintain heat in the winter. These factors translate to less use of heating and cooling systems, which saves significant amounts of energy and money.
Plants grown on rooftops capture moisture in the air, which means that rooftop farms also help reduce the storm water flow that can pollute waterways and overwhelm sewage treatment facilities.
Vertical farms produce crops in vertical layers in a controlled environment. Most vertical farms are created with tall enclosed structures, using height to maximize growth. This innovative approach to urban farming can help to maintain crop production all year round, without relying on favorable weather conditions, soil fertility, or excessive water use.
Establishing vertical farms in urban areas can ultimately help to create a more sustainable environment by contributing to less abandoned buildings, a cleaner atmosphere, better water conservation, and a positive impact on the health of the surrounding communities.
Shipping Container Farming
Recently, using shipping containers as urban farms has become increasingly popular. There is an abundance of shipping containers that are left unused every year, free to be used as indoor farms. These steel structures are durable, versatile, portable and stackable: ready to be placed as a container farm on any site with a strong, level surface.
The versatility of shipping containers provides a range of opportunities to create an enclosed ‘farm’ in any location, from your backyard to corporate campuses. Compared to traditional fixed structures, container farms can be set up in a relatively short period of time.
Using Hydroponic Systems
Innovative new growing techniques have played a key role in the sustainability of urban farming. Hydroponics is the practice of growing plants without soil, a technique commonly used in vertical farming. This method has been shown to have some environmental benefits.
The controlled and closed environment of hydroponic systems usually eliminates the need for pesticides, meaning less poisonous chemicals on the food and plants grown. Hydroponic systems can also recycle water and nutrients, putting less strain on water systems. This sustainable style of growing has become a top choice for many large-scale greenhouses.
Using Aquaponic Systems
Aquaponics is one of the most sustainable methods of urban agriculture. Simply put, this method combines traditional aquaculture with hydroponics. Many farmers have embraced this method to become more environmentally responsible and promote good health within their local communities.
Aquaponic systems can grow many types of food without consuming too many resources. Only a few pieces of equipment in this method actually require power – and in most systems, the water is circulated rather than disposed of after use. Using this style of indoor urban farming, you can ultimately grow more food while using less water, labor and land.
Grow fruits and vegetables in city towers? Advocates give a green thumbs up
By T. A. FrailSMITHSONIAN MAGAZINE | SUBSCRIBE AUGUST 2010
More people than ever are growing food in cities, which happen to be where most of the world’s people now live. In windowsills, on rooftops and in community gardens, they’re burying seeds in Havana, Kinshasa and Hanoi—and in Chicago, Milwaukee and Atlanta. Novella Carpenter’s 2009 memoir, Farm City, trumpets the value of raising chickens, pigs and bees—in Oakland.
Urban farming is a response to a variety of pressures. Large parts of the developing world are facing shortages of water and arable land, the U.N. Food and Agriculture Organization says. Governments and other sponsors have supported urban food-growing projects in Cuba, Colombia, Botswana and Egypt. In the developed world, small-scale urban farms are seen as an antidote to industrialized agriculture’s excesses, including chemical fertilizers that pollute waterways and the high costs, both monetary and environmental, of transporting food to urban markets.
Dickson Despommier, a professor of environmental health sciences at Columbia University, has proposed “vertical farming”: growing food—including fish and poultry—in urban buildings as tall as 30 stories and covering a city block. In his vision, you could eliminate the need for soil by growing plants hydroponically (in a liquid) or aeroponically (in the air). You’d reduce water use and end runoff by recycling water in a closed irrigation system. Transportation costs would be next to nil.
Such a high-rise farm has not yet been built. But in Devon, England, the Paignton Zoo has maintained a hydroponic, controlled-irrigation garden for several months. The yield from its 11,000-odd leafy vegetable plants—lettuce, spinach, herbs—is fed to the animals. The garden takes up 1,000 square feet in a greenhouse, about one-twentieth of what it would require in a field. Kevin Frediani, the zoo’s curator of plants, says its key technology, a system of mobile nine-foot-high racks that help ensure the plants are properly fed and exposed to light and air, could be scaled up.
The maker of those racks, Britain-based Valcent Products Inc., says it is speaking to potential customers in more than 30 countries. “Agriculture has many problems, and it needs to have different methods as part of its armory of solutions,” says Valcent spokesman Tom Bentley. “Vertical farming will be part of that.”
T. A. Frail is a senior editor at Smithsonian.Like this article? SIGN UP for our newsletter
Think there’s only one right way to grow vegetables in Boston, or any city for that matter? Think again! Here at GCG we’ve found the combination of systems that work best for us, but the urban farmer has an endless array of options to customize their urban vegetable garden. Ground level or on rooftops, outdoors or indoors, almost anything is possible.
INSTALLING YOUR GARDEN
WHAT KIND OF BED WILL WORK FOR YOU?
When installing your garden you have several options to choose from: a traditional in-ground bed, a raised bed, or a container. It’s important to take into consideration light, space, financial resources, and how much time you will have to tend your garden when choosing your bed type.
1. In-ground beds. These can be the cheapest option if you have the space for one and the soil is of moderate to high quality (hyperlink here to the soil test GCG page). Make sure that all parts of the bed are easily accessible and that they have a defined border.
2. Raised beds. We use raised beds because they are well suited for the urban environments we place them in; you can install one on virtually any flat surface, the soil won’t easily compact so plants can take root, they are impermanent and can be relocated, you are guaranteed good quality soil, and they can be more aesthetically pleasing than a traditional bed. You can even learn how to build them yourself in our book, The Urban Bounty.
3. Containers. Containers are the most versatile, coming in an endless variety of shapes and sizes, (we use kiddie pools at our b.good rooftop garden!) and they offer the most mobility. However, they are also the most high maintenance on this list because they often dry out too quickly or don’t drain at all! Be careful of the containers you choose for your container garden; you want them to be easy to move even when fully saturated and you want them to be deep enough for what you want to grow.
NO SPACE? GROW UP!
Don’t be afraid to let your imagination go wild when thinking about how to grow vertically, as the possibilities are seemingly endless with vertical gardening…
Now that you know what kind of bed or container you’re going to plant in, you need to decide what you’re going to plant and how you’re going to plant it. Use this free crop map tool to help!
WHY USE SEEDS?
Seeds are a great option for plants such as lettuce, carrots, beets, or radishes that mature quickly or root deeply but starts can be worth it for longer-maturing plants such as tomatoes. When planting from seed, you have a much larger pool of varieties to choose from which can be handy if you’re looking for specific traits. They are also a cheaper option in the event that things don’t go as planned! GCG keeps it local and gets seeds from Johnny’s Selected Seeds in Maine.
WHY USE STARTS?
For the novice farmer, plant starts are an excellent way to ensure that your young seedlings are healthy and have a high chance of survival. The threat of frost is still present in a New England spring and by having a few extra weeks of TLC in a greenhouse, those starts have well established roots and a higher chance of surviving transplant shock in the field. They also allow for a quicker and larger harvest. You can get starts beginning in April and May from local farms and nurseries.
Want to learn more? Order a copy the book The Urban Bounty to learn everything you need to know for a successful urban garden.
On top of a striking new exhibition hall in the southern 15th arrondissement of Paris, the world’s largest urban rooftop farm has started to bear fruit. Strawberries, to be precise: small, intensely flavoured and resplendently red.
They sprout abundantly from cream-coloured plastic columns. Pluck one out to peer inside and you see the columns are completely hollow, the roots of dozens of strawberry plants dangling into thin air.
From identical vertical columns nearby burst row upon row of lettuces; near those are aromatic basil, sage and peppermint. Opposite, in narrow, horizontal trays packed not with soil but coco coir (coconut fibre), grow heirloom and cherry tomatoes, shiny aubergines and brightly coloured chards.
“It is,” says Pascal Hardy, surveying his domain, “a clean, productive and sustainable model of agriculture that can in time make a real contribution to the resilience – social, economic and also environmental – of the kind of big cities where most of humanity now lives. And look: it really works.”
Hardy, an engineer and sustainable development consultant, began experimenting with vertical farming and aeroponic growing towers – as those soil-free plastic columns are known – on his Paris apartment block roof five years ago.
This space is somewhat bigger: 14,000 sq metres, the size (almost exactly) of two football pitches. Coronavirus delayed its opening by a couple of months, but Nature Urbaine, as the operation is called, is now up and running, and has planted roughly a third of the available space.
Already, the team of young urban farmers who tend it have picked, in one day, 3,000 lettuces and 150 punnets of strawberries. When the remaining two-thirds of the vast rooftop of Paris Expo’s Pavillon 6 are in production, 20 staff will harvest up to 1,000kg of perhaps 35 different varieties of fruit and vegetables, every day.
“We’re not ever, obviously, going to feed the whole city this way,” cautions Hardy. “In the urban environment you’re working with very significant practical constraints, clearly, on what you can do and where. But if enough unused space – rooftops, walls, small patches of land – can be developed like this, there’s no reason why you shouldn’t eventually target maybe between 5% and 10% of consumption.”
Nature Urbaine is already supplying local residents, who can order fruit and veg boxes online; a clutch of nearby hotels; a private catering firm that operates 30 company canteens in and around Paris; and an airy bar and restaurant, Le Perchoir, which occupies one extremity of the Pavillon 6 rooftop.
Perhaps most significantly, however, this is a real-life showcase for the work of Hardy’s flourishing urban agriculture consultancy, Agripolis, which is currently fielding inquiries from around the world – including in the UK, the US and Germany – to design, build and equip a new breed of soil-free inner-city farm.
“The method’s advantages are many,” he says. “First, I don’t know about you, but I don’t much like the fact that most of the fruit and vegetables we eat have been treated with something like 17 different pesticides, or that the intensive farming techniques that produced them are such huge generators of greenhouse gases.
“I don’t much like the fact, either, that they’ve travelled an average of 2,000 refrigerated kilometres to my plate, that their quality is so poor, because the varieties are selected for their capacity to withstand that journey, or that 80% of the price I pay goes to wholesalers and transport companies, not the producers.”
Produce grown using this soil-free method, on the other hand – which relies solely on a small quantity of water, enriched with organic nutrients, minerals and bacteria, pumped around a closed circuit of pipes, towers and trays – is “produced up here, and sold locally, just down there. It barely travels at all,” Hardy says.
“It uses less space. An ordinary intensive farm can grow nine salads per square metre of soil; I can grow 50 in a single tower. You can select crop varieties for their flavour, not their resistance to the transport and storage chain, and you can pick them when they’re really at their best, and not before.”
No pesticides or fungicides are needed, no soil is exhausted, and the water that gently showers the plants’ roots every 12 minutes is recycled, so the method uses 90% less water than a classic intensive farm for the same yield. The whole automated process can be monitored and controlled, on site or remotely, with a tablet computer.
Urban farming is not, of course, a new phenomenon. The mayor of Paris, Anne Hidalgo, aims eventually to have at least 100 hectares of rooftops, walls and facades covered with greenery – including 30 hectares producing fruit and vegetables. A programme called Les Parisculteurs invites local groups to come up with suitable projects for up to a dozen new sites every year.
Inner-city agriculture is booming from Shanghai to Detroit and Tokyo to Bangkok. Strawberries are being grown in disused shipping containers; mushrooms in underground carparks. Not all techniques, however, are environmentally friendly: ultra-intensive, 10-storey indoor farms that have sprung up in the US rely on banks of LED lighting and are major consumers of energy, Hardy says.
Aeroponic farming, he says, is “virtuous”. The equipment weighs little, can be installed on almost any flat surface, and is cheap to buy: roughly €100 to €150 per sq metre. It is cheap to run, too, consuming a tiny fraction of the electricity used by some techniques.
Produce grown this way typically sells at prices that, while generally higher than those of classic intensive agriculture, are lower than soil-based organic growers. In Paris, Nature Urbaine should break even, Hardy estimates, some time next year – a few months later than planned because of the pandemic.
There are limits to what farmers can grow this way, of course, and much of the produce is suited to the summer months. “Root vegetables we cannot do, at least not yet,” he says. “Radishes are OK, but carrots, potatoes, that kind of thing – the roots are simply too long. Fruit trees are obviously not an option. And beans tend to take up a lot of space for not much return.”
But Agripolis runs a smaller test farm, on top of a gym and swimming pool complex in the 11th arrondissement, where it experiments with new varieties and trials new techniques. A couple of promising varieties of raspberries are soon to make the transition to commercial production.
Urban agriculture is not the only development changing the face of farming. As with almost every other sector of the economy, digitisation and new technologies are transforming the way we grow food.
Artificial intelligence (AI) and the internet of things are beginning to revolutionise farming, from driverless, fully automated farm machinery that can sow seeds and fertilise and water soil with maximum precision to systems that monitor exactly how healthy individual animals are and how much they are producing (a concept known as the “connected cow”).
Other AI systems analyse satellite and remote ground sensor data, for example, to monitor plant health, soil condition, temperature and humidity and even to spot potential crop diseases.
Drones, too, have multiple potential uses on farms. With the world’s bee population in steep decline due to global heating, pesticides and other factors, drones are increasingly being used to pollinate crops fields and fruit orchards. To avoid wasting pollen by wafting it randomly at crops, or the damage to individual flowers caused by drones rubbing against them, scientists in Japan have developed a system in which a drone uses what can only be described as a bubble gun to blow balls of specially formulated liquid containing pollen at individual blossoms.
With global food production estimated to need to increase by as much as 70% over the coming decades, many scientists believe genetic editing, which has already been used to create crops that produce higher yields or need less water to grow, will also have to play a bigger role.
The technique could help build plant and animal resistance to disease, and reduce waste. For example, with methane known to be a stronger greenhouse gas than carbon dioxide, research is under way into the stomach bacteria of cows in the hope that tweaking animals’ gut microbes may eventually allow them to produce not just more meat, but also less gas.
Urban farming of the kind being practised in Paris is one part of a bigger and fast-changing picture. “Here, we’re really talking about about building resilience, on several levels – a word whose meaning I have come to understand personally,” says Hardy, pointing to the wheelchair he has been forced to use since being injured by a falling tree.
“That resilience can be economic: urban farming, hyper-local food production, can plainly provide a measure of relief in an economic crisis. But it is also environmental: boosting the amount of vegetation in our cities will help combat some of the effects of global heating, particularly urban ‘heat islands’.”
Done respectfully, and over time, inner-city agriculture can prompt us to think differently both about cities, by breaking down their traditional geography of different zones for working, living and playing, and about agriculture, by bringing food production closer into our lives. “It’s changing paradigms,” says Hardy.
100 days to save the Earth …
… we’re all in. Are you? On November 4, a day after the presidential election, the US will formally withdraw from the Paris agreement on constraining global heating. It’s urgent that we tell the world what this means, and the Guardian is pulling out all the stops to do so. Will you help us by supporting our journalism?
Millions are flocking to the Guardian every day. Financial support from our readers is crucial in enabling us to produce open, fearless, independent reporting that addresses the climate emergency. It helps sustain the freedom we have to present the facts comprehensively, explain the details as they unfold, and interrogate the decisions made.
At this pivotal moment for our planet, our independence enables us to always inform readers about threats, consequences and solutions based on scientific fact, not political prejudice or business interests. This makes us different. And we are equally determined to practice what we preach: we have divested from the oil and gas sectors, renounced fossil fuel advertising and committed to achieving carbon neutrality by 2030.
We believe everyone deserves access to information that is fact-checked, and analysis that has authority and integrity. That’s why, unlike many others, we made a choice: to keep Guardian reporting open for all, regardless of where they live or what they can afford to pay. Our work would not be possible without our readers, who now support our work from 180 countries around the world.
Technology can help urban agriculture meet the food security requirements of the future, says Paul Teng.
According to UN-Habitat, the UN agency for human settlements, the 21st century will be the century of urbanisation. The year 2008 saw, for the first time in history, the world’s urban population overtake its rural population.
As the world becomes increasingly urban, food demand will come mainly from people living in cities, while there will be fewer rural farmers producing food on less land with less water. Furthermore, the locus of poverty is likely to shift from rural to urban areas. Urban and peri-urban areas can and will have to play a bigger role in food security. But to accomplish this requires supportive enablers such as new farming approaches and technologies, new thinking and policies by policymakers, politicians and consumers willing to accept new food types and unconventional ways of food production.
With global food demand estimated to increase by at least 50 per cent by 2050, it is necessary to ask what and where else can be tapped to produce the quantum of food needed.
“Urban centres should strive to become food producers, and not just consumers”
Several years ago (2014), this author asked, with respect to food security, whether cities should be part of the solution and not just be viewed as the problem . Much progress has been made since in affirming the contribution of cities to growing food close to where it is needed. Urban farming, especially in community gardens, has further helped improve the nutrition quality of inner city diets, an aspect of food security causing grave concern with the rise in non-communicable diseases.
A traditional rural responsibility
Traditionally, the practice of agriculture has been considered a rural phenomenon.
However, with more people now living in urban areas, food insecurity has become an urban phenomenon. Urban centres should strive to become food producers, and not just consumers. Urban agriculture can help cities achieve a high level of self-sufficiency in at least some of the key food products that its inhabitants consume.
Urban agriculture is considered as the growing of plants and the raising of animals within and immediately around cities. It is estimated to currently contribute 5 – 20 per cent of the world’s food needs .
The most striking feature of urban and peri-urban areas, which distinguishes it from rural agriculture, is that it is integrated into the urban economic and ecological system. Urban agriculture is embedded in — and interacts with — the urban ecosystem and its resources. Such linkages include the use of urban residents as labourers and the use of typical urban resources (like organic waste as compost and urban wastewater for irrigation), direct links with urban consumers, direct impacts on urban ecology (positive and negative), competing for land with other urban functions, being influenced by urban policies and plans, etc.
About 800 million people are now involved in urban agriculture and contribute to feeding urban residents. Most of these people are from the developing countries of Asia and Africa. Of these, 200 million produce for the market and 150 million work full-time . Urban agriculture activities range from relatively low-tech community gardens and small farms using conventional techniques, to highly sophisticated plant factories (with enclosed environments and artificial light) and bioreactors producing cell masses. Urban farms can contribute to rehabilitation of communities suffering from economic dislocation, and to providing an alternative use of the consequential abandoned land.
Urban agriculture in developed countries has seen significant growth in recent years thanks to high value-added agriculture, the promotion of the ‘garden city’ concept, expansion of community gardens and roof-top planting and use of urban agriculture to promote environmental sustainability. Contamination from particulate air pollutants has so far not been an issue in the cities concerned because of chosen locations or exclusion technology such as “plant factories”. In modern cities like New York and Singapore, urban agriculture is seen as an application of high technology (especially digital, mechanical) backed by rigorous science to create new food supplies and employment.
Urban agriculture in developing countries is less pronounced but has great potential for growth. The success of urban agriculture in cities such as Hanoi, Shanghai, Beijing, Mexico City and Dakar has shown how urban farming can contribute to poverty reduction, food security, improvements in nutrition, increased income, environmental protection and increased awareness of the importance of agriculture through on-site agro education. In these cities, the Resource Centres on Urban Agriculture and Food Security Foundation, Netherlands, has estimated that up to 80 per cent of fresh vegetables may come from a city such as Hanoi and immediate periphery.
Exciting new approaches and technologies
Agriculture in the 21st century is strongly influenced by new scientific tools (molecular markers, gene editing, etc.) and new technologies (digital, mechanical, biological) which have resulted in a set of powerful technology outcomes with applications in rural and urban situations. In a previous SciDev.Net article , I listed some:
Agronomy and agricultural biotechnology to innovate inputs for crop and animal agriculture such as seeds, pest control, seeds with new genetics, microbiome and animal health
Mechanisation, robotics and equipment such as on-farm machinery, automation, drones guided by GPS or GIS systems, environmental sensors, and growing equipment
Farm management software, Internet of Things systems with sensing and intervening – these include environmental, farming data capture devices, decision support software, big data analytics and miniaturised portable applications
Novel farming systems such as indoor farms, plant factories with controlled environment, aquaculture systems, and grow-out facilities for insects, algae and microbes
These technologies have been used separately or in combination to farm in open spaces, shaded shelters and completely controlled environments. Environment sensors for temperature and moisture have been deployed by urban farmers in open fields or shaded farms for many years, often accompanied by computer software which perform analytics and provide advisories.
One of the most ‘Disruptive Technologies’ in urban farming is the ‘Plant Factories with Artificial Lighting’ or PFALs which grow vegetables in trays vertically stacked within a room in which the environment (air, light, temperature, and humidity) is controlled to provide optimal plant growth.
Lettuce plants about to be harvested at the VertiVeggies Pilot Plant Factory. Image credit: Paul Teng. LED lighting is used to optimise the plants’ photosynthetic capacity for vegetable growth and development and reportedly have shortened time-to-harvest by almost a third. The company NewBean Capital, Singapore, estimated that there were over 450 PFALs in commercial production in Asia in 2016, mainly located in China, Japan, Singapore and South Korea. The PFALS produce more kilograms of vegetables per unit area and use less water, although energy efficiency is still to be improved. But their unique proposition is that vegetables can be grown year-round and for the longer term can buffer against climate change.
On the horizon for urban food production is the use of cell culture technology to produce vegetable products and even animal meat (colloquially referred to as ‘clean meat’) in large bioreactors housed indoors. This author participated in the first International Plant Cell Technology Industry Summit in October 2019 in Chongqing, China, and witnessed the government’s investments to establish this as a viable industry to produce food ingredients and actual consumable food.
Part of food future
With more and more people living in urban areas, the international community needs to consider urban food security and the role of urban agriculture in its own right but still recognise its strong inter-relationships to the wider discourse on food security and to the global food supply chain.
While there continues to be a strong interdependence between urban and rural areas, the urban dimensions of food production merit distinct attention and focus from national governments. In order to successfully address the growing problem of urban food security in the face of food price increases, policies and programmes need to better reflect the urban context.
Appropriate support mechanisms such as political, legal, operational and regulatory frameworks need to be put in place to facilitate urban agricultural activities, move them into the formal economy, and address food safety and health concerns. Related to the latter two is the issue of food waste and recycling this into circular food systems which support sustainability approaches.
Urban agriculture as an integral socio-economic activity provides many lessons for similar geographies such as small island states, of which there are many in the Caribbean and Pacific regions of the world.
The world will need much more food in 2050 that is produced using sustainable practices under huge climate change challenges. The traditional countryside is not enough and spaces in cities need to be tapped to ensure food and nutrition security for all. Urban agriculture is coming to age as a serious activity to complement food production in the countryside and is like to become even more important as technology advances and climate variability forces more farming in controlled environments.
Just because you live in the city, that doesn’t mean that starting a business in the agriculture industry is out of the question. Urban farming is bringing food production into busy, populated areas, and it’s more popular than ever.
What is urban farming? Urban farming is all about producing food inside city limits. It has its challenges, but it also offers many benefits like increased food security, decreased waste, community involvement, and more.
In this article, you’ll learn what urban farming is, how and what urban farmers grow, what the benefits of urban farming are, some different practical approaches to urban farming, and more.Article Contents:show
What Is Urban Farming?
In the most basic of terms, urban farming is simply producing or growing food in a city or other heavily populated areas. It shouldn’t be confused with community gardening, subsistence farming, or homesteading.
The big difference between urban farming and these separate categories is that urban farming assumes a profit motive and that it’s undertaken as a commercial enterprise.
This separates urban farming out from gardening activities where the end goal is personal consumption.
That doesn’t necessarily mean that urban farming is all about big business. Normally it’s quite the opposite. You don’t need a big piece of land, or even a corporation to start an urban farm.
You can begin by yourself, by partnering with some friends, or even as a nonprofit entity.
Urban farming gives people a chance to pursue their passion for agriculture who may not be able to move out of the city and buy a piece of land in the country. Either for financial, logistical, or practical reasons.
The food produced on urban farms can be sold at farmer’s markets, direct to restaurants or grocery stores, or through a CSA (community supported agriculture.)
As people are becoming more educated about their food, where it comes from, and the effect that transporting food can have on climate change, there’s an increasing demand for locally-grown, sustainable, organic produce.
Urban farming can be found in pretty much every area of the city.
In public spaces and parks, next to apartment buildings and condos, on top of rooftops, next to restaurants and other businesses, in backyards, at schools, and anywhere else you can think of.
So people have come up with many unique approaches to urban farming that work in a variety of different conditions and settings.
1. Vertical Farming
Vertical farming involves growing crops in layers that are stacked vertically. This can be accomplished by growing on shelving, or on specially-modified pallets against fences or walls.
Vertical farms can be housed in abandoned mineshafts or other underground tunnels, inside of buildings, or in shipping containers.
It’s usually combined with other innovative techniques like aquaponics or hydroponics in a climate-controlled environment.
Vertical farming can make a square foot of space orders of magnitude more efficient at producing food, since many plants don’t need a lot of vertical space to grow.If you can stack three or four shelves of plants on top of each other, suddenly you’re growing 300% to 400% more plants than what you could conventionally fit into the same amount of space.
Hydroponics is any system for growing plants without soil. Instead, nutrients are added to water that plants are immersed in, or that regularly washes over the roots of the plants.
Gravel, perlite, or other materials can be used to provide more physical support for the plants.
Hydroponic systems can use chemical fertilizers, or organic matter like manure.
Since water in hydroponics systems is recycled and reused, it can save on water usage for growing crops.A conventional farm requires about 400 liters of water to grow a kilogram of tomatoes, while a hydroponic system can grow the same amount using only 70 liters of water.
Hydroponics can be used to grow plants where the conditions are too harsh to grow them in soil. It may even be used to grow plants in space when humans decide to go to Mars!
There are many different hydroponics techniques:
A static solution culture contains unaerated nutrients in a container.
A continuous flow solution passes nutrients over the roots constantly.
Aeroponics uses a fine mist or aerosol to keep plant roots moist while they’re suspended in air.
Ebb and flow systems flood a tray full of growing medium at regular intervals and then allow it to drain completely. This is done with a pump that’s set on a timer.
Aquaponics is any system that combines conventional aquaculture (farming fish or other sea life) with hydroponics. This creates a symbiotic relationship between the fish and plants.
Fish eat food and produce ammonia. Helpful bacteria in the water converts ammonia into nutrients for the plants.
The plants absorb the nutrients, which act like a natural fertilizer. And water gets constantly recirculated through the system so the cycle can continue.
Tilapia is one of the most popular types of fish for using in an aquaponic environment. They’re tasty and can be sold as they mature to make another source of income besides the plants that are being grown.
Leafy green vegetables tend to work the best and be the easiest to grow in an aquaponic system, although you can grow a wide variety of other plants like cucumbers, peppers, and tomatoes as well.
4. Shipping Container Farms
If the weather outside isn’t conducive to growing, or even if you just want a more stable pest-free environment for growing, shipping container farms are a great option.
They don’t take up small space and you can fit one in almost anywhere, even just in an unused corner of a parking lot.
Special systems can be installed for lighting, climate control, as well as other factors to create a perfect growing environment.
Racks of shelving can be installed to fully maximize vertical space inside the shipping container.
Most commonly mushrooms, microgreens, or leafy greens are grown because these crops don’t take up much space and also fetch a premium.
They might seem too small to be practical for some people, but a shipping container is actually large enough to generate a full-time income from urban farming with the right systems in place.
5. Rooftop Farming
In the heart of the city, green space on the ground comes at a premium if there’s any available at all. But the rooftops of skyscrapers and apartment buildings represent a largely underused resource.
Raised beds, and even greenhouses or animals like chickens on rooftops are all a possibility. It all depends on what the owner of the building is comfortable allowing you to do with the space, and what your local laws are.
Care should be taken to make sure adequate support is in place before starting a rooftop farm.
Soil can weigh thousands of pounds when you have it all in one place, so care needs to be taken with how a rooftop farm is arranged to ensure the roof can support the load.
Setting up or dismantling a rooftop farm can be difficult, as absolutely every part of the operation needs to be gradually taken up onto the roof using an elevator if you’re lucky, or stairs if you aren’t.
That includes bringing up all the soil you need, as well as something to contain it.
Mushrooms aren’t a crop that immediately comes to mind for most people. But for urban farming, they’re an awesome choice.
The science behind how mushrooms are grown eludes most people, and it can seem like magic that people are able to reliably grow mushrooms, but it’s really more simple than you might expect.
For mushrooms like oyster mushrooms, a large, clear plastic bag is filled with a growing medium like coffee grounds and straw. This is then inoculated with mycelium of the mushroom species you’re trying to grow.After an incubation period where the mycelium is allowed to fully colonize the bag of growing materials (basically like a plant establishing a root system), holes are cut in the bag to expose it to air, and the fruit bodies of the mushroom will begin to grow.
There are two things that can be a challenge for newer mushroom growers.
The first is avoiding contamination. Mold or other fungi that you don’t want can infect grow bags and compete with the species you’re trying to grow.
If they win and overtake the mycelium, it can ruin a whole batch of mushrooms.
The other is keeping growing conditions just right for the mushrooms, especially while they are fruiting. Especially temperature and humidity.
If humidity is too low, it can cause the mycelium to dry out and not produce any mushrooms. If it’s too high, it can become a breeding ground for mold and mildew.
Using fans to maintain airflow can help keep things under control.
You get a very quick turnaround time with microgreens compared to conventional crops. 7 to 14 days for most varieties of microgreens, as opposed to 90 days or more for some traditionally grown crops like peppers or pumpkins.
Despite their small size, microgreens are absolutely packed full of nutrients, and are becoming a popular choice for health-conscious people to add to salads or smoothies.
Chefs also like to use microgreens as a garnish because they give a nice aesthetic appeal.
Microgreens take up very little space and can be grown in a single room or shipping container. The process is normally quite automated, including watering and LED lighting all done on set timers.
With the right urban farming techniques, you can actually make a full-time income on a space as small as 1/3rd or 1/4 of an acre. Backyard farms are also referred to as market gardens.
The best part about backyard gardens is that you don’t even necessarily need to own the land to start growing on them.
For most people, their yard is just sitting unused, and cutting the grass and maintaining it can be a chore more than anything else.
A good proportion of homeowners will be happy to let you grow food in their backyard in exchange for a portion of your harvest or the income you earn, others may rent you the space for a set fee for the season.
Like with most other types of urban farming, space is at a premium when you only have a small yard to work with. So it’s important to pick compact crops like greens that sell for a high price.
Where city bylaws allow, backyard gardens can even include small livestock like chickens, as well as beekeeping.
The Benefits of Urban Farming
Urban farming comes with a bunch of benefits over conventional farming. Some of them may be obvious, while others aren’t so intuitive.
Here are some reasons why I think urban farms offer a lot of value to any community that they’re a part of.
1) Increased Food Security
Urban areas can often form what are called food deserts, which are areas where it’s difficult to buy good quality or affordable fresh food.
If there aren’t any grocery stores in your area and you don’t have a car, the only food sources you might have within walking distance could be fast food restaurants and convenience stores.
Urban farms can provide food to low-income individuals who need it the most.
2) Creates Fresher, Healthier Foods
When you buy a tomato or many other types of produce at the supermarket, you’re getting something that was picked underripe.
It’s a necessity, since produce needs to be shipped across the country, and it can often take several days for it to pass through all of the distribution channels and arrive at its final destination.
Urban farming creates fresh produce closer to where it’s ultimately consumed. That means less food miles traveled, which is great for cutting down on carbon emissions to help fight climate change.
Food from urban farms is far more likely to be perfectly ripe, more nutritious, and produced in season. Whether it’s fruits, vegetables, or herbs.
As a farmer, the upside to this is that customers are willing to pay a premium for freshness and local production.
Public health is a huge concern in the inner city, where people often suffer from malnutrition or other diet-related health problems.
Giving people nutrient-dense healthy alternatives will help reduce the risk of obesity, diabetes, heart disease, and other conditions in the area. Plus tending to the farm itself provides exercise to those who are working in it.
3) Urban Regeneration and Use of Under-Utilized Spaces
Urban farming is able to put land to use that is otherwise undesirable or can’t be put to good use. An urban farm breathes new life into older run-down communities.
It creates more green space, which is something that cities could desperately need. Greenery creates a relaxing feeling to the community and has a more aesthetic appeal than an empty lot.Areas with community gardens and urban farms also increase property value. One study found that gardens in the area raised surrounding property values by nearly 10% within five years.
4) Community Involvement
Urban gardens can do more than just produce an abundance of fresh healthy foods. It can bring the residents of the area together as a community.
For urban farming nonprofits, a lot of social activity and organization is required. And everyone will have a vested interest in seeing the project succeed once they start to put their own time and energy into it.
Urban farms can help to create a sense of belonging among people that would otherwise be isolated from one another.
Urban farms can give back to the community by holding tours or workshops to teach children and adults alike in the area where their food comes from.
It’s a learning opportunity for picking up various gardening techniques and other information that people may not have access to.
Urban farms can integrate with local restaurants or cafes to benefit both parties.
The farm gets a steady customer to buy its produce, and the restaurant can use the fact that it buys locally-sourced produce from the community as part of its advertising and appeal.
5) Makes Efficient Use of Land
Think about how many areas of the city are sitting unused and being wasted.
Hydroponic systems, vertical or rooftop gardens, and other techniques can be used to fit in a lot of extra food into any free urban space that’s available.
Urban farmers come up with innovative and efficient solutions to the problems that growing in the city can challenge them with.
6) Economic Growth and Job Creation
As your urban farm grows, you may be able to take on multiple plots throughout the city. Once it’s more than what you can manage yourself, you can bring on employees or volunteers to help keep things running smoothly.
Low-income people without much education in the inner city might not have the opportunity to get many jobs.
Urban farms can offer them valuable skills and education in addition to a steady source of income, even if it is seasonal work.
Hunger and poverty are common themes in an urban environment. But urban farms can help to support the community and stimulate its economy by circulating income in the region.
7) Less Food Waste
Some food waste occurs because stores stock more fresh food than what they can sell before it goes bad. Other times, consumers buy produce and it goes bad before they’re able to consume it.
Urban farms help cut down on both of these types of food waste. People can harvest only what they are going to eat that day or within a few days, so they’re less likely to waste food.
There is less of a disconnect between where your food comes from and what you eat.
8) Less Investment Required
Buying a conventional farm is a huge undertaking. Even if you just want a small farm with an acre or two, you’re looking at hundreds of thousands of dollars.
Even to lease farmland from another farmer for a season, you’re looking at some major expenses.
Urban farms take up far less space, and initial infrastructure and setup costs is often drastically lower than a traditional farm as well.
9) Water Conservation
Urban farming saves water a couple of different ways.
First, urban farms tend to use irrigation systems on timers, hydroponic systems, or other methods that allow them to use 2/3rds less water than what a conventional farm would need to achieve the same output.
Urban farms also prevent water runoff and other issues that would be present if the farm wasn’t there.Farms can set up catchment systems to collect rainwater from nearby buildings, and water their crops 100% from rainwater.
Examples of Urban Farming
For most people, Curtis Stone is the go-to guy when it comes to urban farming, and his Youtube videos and other materials are often the primary way that people find out urban farming is even an option.
Curtis operates his urban farming business called Green City Acres, which has several urban farms located around Kelowna, British Columbia, Canada.
He has a Youtube video with over 300,000 subscribers and hundreds of videos that are an amazing resource if you’re just getting started with urban farming.
He teaches practical techniques, as well as does in-depth interviews with other growers to understand what’s working for them and what isn’t.
You can buy his book entitled The Urban Farmer on his website. He also does in-person courses and offers online courses on topics like growing microgreens, and passive solar greenhouse design.
He also has a membership website fromthefield.farm where he does in-depth videos about sustainable agriculture every week.
In addition to growing food to earn an income, Nature’s Always Right also has the goal of teaching as many people as possible about regenerative farming techniques, and helping them to grow their own healthy food on a small scale using no-till methods.
Located in London, UK, FARM: uses a variety of urban farming techniques including a rooftop chicken coop, aquaponic fish farming, and small-scale vegetable farming using a polytunnel as well as a high-tech indoor allotment
The goal of the project is to teach Londoners that it’s possible for people who live in the city to grow food without having large amounts of space. It has been operating since 2010.
Where Does Urban Farming Take Place?
The name urban farming conjures up images of food being grown right in the middle of the inner city or downtown.
While that’s certainly a possibility, there’s no characterization on exactly how dense or populated an area needs to be to qualify as urban farming.
But it generally includes properties and land right up to the outer edge of the city.
Urban farmers grow in backyards, on top of the roofs of apartments and skyscrapers, on vacant or abandoned properties or land, and plenty of other places.
Some cities are even setting aside portions of parks or other open land to allow urban farmers to use.
It’s critical to take your city’s zoning and by-laws into account before you get started with urban farming. What’s allowed can vary from place to place.
Most cities have restrictions on any kind of livestock being kept within their limits, although some places make exceptions for backyard chickens, rabbits, or even beekeeping.
Some cities will allow you to grow vegetables in your front yard, while others won’t. Other locations will limit what kinds of retail sales you can do out of homes and other non-commercial properties.
While states and provinces may have specific licenses and certification that are required to operate your urban farm, like safe food handling or WHMIS.
Understandably, producing people’s food comes with a lot of liability and safety issues, so municipalities tend to err on the side of protecting the consumers.
What Products Do Urban Farmers Grow?
As mentioned, it’s much harder for urban farmers to try to raise livestock like cattle, pigs, and sheep within city limits, just because of the legal restrictions.
But most other things that any conventional farm is capable of producing are on the table.
Urban farmers grow vegetables, root crops, fruits, and even grains. As well as herbs and medicinal plants, or purely ornamental varieties of plants.For a brand new urban farmer looking for an entry point in the market, I would suggest 3 crops that are fairly easy to grow and offer good returns: Mushrooms, microgreens, and leafy greens.
All three of these products are more perishable than a lot of other types of crops.
That gives urban farmers a big advantage when it comes to freshness and quality, compared to larger companies that might need to ship their product several days before it reaches its destination.
Both microgreens and mushrooms can be grown indoors and take up very little space. Many urban farmers are able to grow these crops in converted shipping containers, or anything else that’s basically the equivalent size of one large room.
Leafy greens like arugula and spinach fetch high prices due to their short shelf life, but require growing outdoors or in greenhouses or wind tunnels.
Market garden techniques and practices can be used to produce large amounts of food in a tiny space, however.Some urban farmers are able to make as much as $100,000 per year on just a 1/3 acre piece of land if they have the knowledge and conditions needed.
Generally, as an urban farmer, you want to highly specialize on crops and different varieties that aren’t normally available from regular distributors and large-scale farms.
What Tasks Do Urban Farmers Perform?
As an urban farmer, you’ll need to wear a lot of different hats, and it might be on you to perform all the roles that your business requires all by yourself.
In addition to just growing the food, urban farmers need to be experts when it comes to marketing and connecting with buyers.
It doesn’t matter how great your food is or how much you can grow, if nobody is willing to buy it!
It’s up to you to pitch your product to shops and restaurants in your area, as well as man your booth at the farmer’s market every weekend.
Urban farmers usually end up doing all of their own deliveries as well. You’ll need a climate-controlled van to get all of your produce to customers in a timely manner.
Although some urban farmers even deliver their products via bicycle and pull their inventory on a trailer behind them.
You’ll also need to do all of the administrative work for your business like bookkeeping/accounting, filing paperwork, and more. Combined, all of these tasks can easily add another 10 hours on to your work week.
Even if you’re living in the city, you can earn a full-time income from your passion for agriculture by making use of urban farming techniques.
Crops like edible mushrooms and microgreens take very little space to grow, but they offer high margins.
Techniques like vertical farming and aquaponics can make tiny spaces like shipping containers or rooftops into full-scale operations that are capable of providing food to nearby neighborhoods.
Urban farming isn’t just profitable, but urban farms have a number of benefits for the communities they’re in as well.
They increase food security and give people access to fresh, nutritional food that they might not be able to buy otherwise.
Urban farms can also help boost economic growth in an area and provide jobs. They can also help to create a sense of community.
If you’ve ever wanted to start farming but can’t see yourself giving up the city life to move to the country, urban farming offers a great alternative that will allow you to follow your passion.
The different methods of urban farming include community-supported agriculture, city farmers’ markets, indoor farming, vertical farming, and a host of other alternative means to produce or deliver food in an urban environment. Understanding the tradeoffs from an economic, health and safety, and environmental perspective is imperative to selecting the right urban farming options for a particular locale. This will vary depending on location, alternative sources of food, and local income levels.
RUAF cites that by 2020, developing countries like Africa, Asia, and Latin America will find three-fourths of their populations in urban areas. These areas often will not be able to employ that population effectively, provide food reliably, or manage waste or wastewater properly. Urban agriculture is one way to address these issues in poorer nations.
In addition, more developed countries like the United States continue to lose arable farmland at an alarming rate. In fact, scientists estimate that the world has lost one-third of its fertile farmland in the last 40 years.
Types of Urban Farming
As both technology and the push for sustainability continue to develop, many urban agricultural ideas have surfaced. Here are some of the most popular and innovative ones.
Community Supported Agriculture
Perhaps one of the earliest efforts to keep fresh produce local, community-supported agriculture (CSA) systems allow local food producers to serve a set number of urban members who agree to pay a subscription fee for a share of locally grown produce. CSAs can successfully reduce shipping costs and related carbon emissions, as well as boost a local community’s economic development.
In some neighborhoods, housing complexes, or even downtown rooftops, a community garden can be planted by those who live and work nearby. Often, these gardens help clean the air, absorb carbon emissions, and provide healthy, fresh food for those participating. Such endeavors are usually run by volunteers who share in the garden’s production.
The precursor to the high-tech indoor farming developments that are currently growing in popularity are simply greenhouses. By controlling light, temperature, fertilization, and other growing conditions in an enclosed area, many have increased their germination and yields. Today’s Controlled Environment Agriculture (CEA) technology artificially controls temperature, humidity, light waves, and gases to maximize the growth of particular plants, medicines, and foods. In addition, indoor farms may eliminate the need for herbicides and pesticide usage. Technology also allows urban farms to embrace preventive maintenance requirements within agriculture.
Vertical farming is a means of urban food production that grows produce vertically, instead of on a single, horizontal plane as conventional or greenhouse farming may use. The major benefit is the ability to produce more food in a tighter space, especially in urban environments where space is a premium. Vertical farming is commonly part of skyscrapers, or repurposed warehouses in the city.
Benefits of Urban Farming
Urban farming can benefit a community in many ways. When urban farms incorporate more green space on rooftops or within pockets of the city, the community benefits from cleaner air, fresher food, and a reduction in the greenhouse effects of urban areas. In addition, overall carbon emissions are lowered because local food does not need to be transported and distributed.
Besides many environmental benefits, urban farms can create fulfilling jobs for city dwellers and economic growth within an urban environment. Agricultural endeavors tend to appeal to people looking for a slower, more relaxing way to spend time within the typical fast-paced city life. As a result, urban farms can help build community and enhance relationships. It can also create an opportunity to search for innovative and unique solutions to overall food production and distribution challenges that will grow into the future.
Food security and education about how and where food comes from is yet another benefit of urban farms. In lesser developed countries, urban farms can alleviate poverty by providing employment opportunities that produce food for the local community, as well.
Could urban farming be a viable way to improve resilience and lower emissions in our cities, or are the challenges of growing enough crops to support local populations too great? We asked the experts…
“It will ease the disruption wrought by climate change on crop growing”
Urban agriculture is an umbrella term that covers everything from allotments and community gardens, to more high-tech solutions such as hydroponics or underground farming. The gap between the urban population and the food system has been growing. With the world facing a climate emergency, that gap is now being looked at seriously: it can reduce emissions, have huge benefits for urban environment, and provide social benefits, too.
Furthermore, it could add huge value to the rural sector. Climate change is going to have significant negative impacts on yields in the global south: urban agriculture can prop up that system. So I can see a lot of potential, and businesses are starting to get involved and looking to invest.
Michael Hardman is co-founder of the Food Geographies Research Group at the Royal Geographical Society, and a senior lecturer in geography at the University of Salford
“You won’t be able to feed whole cities, but it can help ease the burden”
By 2030, there will be 9 billion people on the planet, and researchers suggest we need to increase food production by 60% to feed them. Meanwhile, the number of pollinating insects is falling – 40% of insect species are in decline. So if the food system doesn’t work, we need to find one that does.
One possibility is hydroponics: systems in which the roots are not in soil, and plants are watered with nutrients. Artificial light enables hydroponic farmers to grow crops indoors all year round, and you can also grow vertically, so you can get much higher yields per square metre.
There are downsides. Although they’re space efficient, these systems may not be energy efficient. And to grow at the scale required to feed the population you would need an enormous amount of infrastructure.
I’m not saying cities will become self-sufficient. But plenty of urban agriculture is already happening in Africa, where rough estimates suggest that one-third of the food needed is produced in cities or on the urban fringe. And reducing the pressure we put on the environment is only good.
Silvio Caputo is a senior lecturer at Kent School of Architecture and Planning
Tell us the truth…
Do you think RICS is doing enough to raise awareness of, and help tackle, the climate crisis?YesNoSubmit your answer
“Growing crops close to population centres helps to reduce food miles”
My business partner and I realised there are huge problems with the way we currently produce food – so if we wanted to have a positive impact in the world, food was the place to do it. We decided aquaponics might be a sustainable way of growing in cities. It’s a type of hydroponics, which uses fertiliser from fish, but it has the potential to grow food in cities, right next to where consumers live.
That would give people the freshest food possible, reducing the need for transport and packaging. Plus, growing indoors isolates agriculture from the effects of the climate. But there are open questions about energy requirements: you’ve got to ask where the power comes from.
There are three elements to what we do: we’re an education company, teaching children about organic agriculture; we carry out research to explore the best way of using these systems in cities; and obviously we grow crops. This last element is the one we currently do the least, but we’re ramping up to do small-scale commercial growing.
Jens Thomas is co-founder of Liverpool-based social enterprise Farm Urban
You may also be interested in:
By 2030, the world will require 40% more water, 50% more food, 40% more energy and 40% more timber and fibre. The only way we can meet these demands is by managing our ecosystems smartly and sustainably.
UN Environment Programme
“Beyond supplying food, there are also educational and wellbeing benefits”
Greensgrow is a non-profit farm and garden centre, located in a very dense, depressed part of Philadelphia’s urban core. It started in the late 1990s on a brownfield site, and today we have one full city block; part of the site is also set up for animals.
We grow about half of what we offer on the farm stand ourselves. The other half comes from regional farms. Urban farms won’t be able to feed an entire city, but they can support a huge system of local farms, and help fill in the gaps. The limitations of the site include a lack of space and light, as well as just dealing with waste and pests.
One of the main purposes of urban agriculture is education: explaining the relationship between our food and the environment. The other big thing is wellness: farms attract birds, butterflies, caterpillars and more. There’s a sense of smell and sensuality in that landscape that is hard to find in an urban park.
Meg DeBrito is executive director at Greensgrow, Philadelphia, US
This article originally appeared in the Precision issue of Modus (Jul-Aug 2019). The opinions expressed here are those of the author and do not necessarily represent the views of RICS.
The practice of urban agriculture is incredibly variable. There are a tremendous number of current technologies and systems for developing urban agriculture on both large and small scales, and on surfaces that are both horizontal and vertical. It demands a certain ingenuity, or creative spirit, to take on farming of all types in the city and the best practices are the ones that take advantage of existing opportunities and infrastructures.
LARGE-SCALE FARM IN CUBA
Large scale projects in urban agriculture are less common because they bring up complex political and social issues regarding urban land use, ownership and labor. Cuba is the best, and perhaps only example, of a large scale urban agriculture movement that has been formally deployed. There are also other large scale instances of urban agriculture in other developing countries where it is an issue of survival. There aren’t any examples in the United States currently, but there is a project in the works in New York called the Five Borough Farm. This is a pilot project that is looking to consolidate disused, under-used or vacant urban land in New York City, for the purpose of creating the first city-wide urban agriculture plan in the country. The land under discussion is city owned, and the intention of the project, after completing a survey of existing urban agriculture initiatives throughout the five boroughs, is to leverage the available land base and those existing projects to show the city how it can support and improve the urban agriculture movement in New York through policy changes.
There are countless examples of people producing small amounts of food (vegetables, a fruit tree, etc.) for personal consumption in their own yards. There are also many examples of community based agriculture all over the world. These community gardens are large garden areas in a common space where each tenant has their own area to garden.
On the Roof
UNCOMMON GROUND RESTAURANT ROOF GARDEN
Since open land in cities that’s available for growing crops is scarce, many have started growing crops on the other horizontal surface in cities that are in abundance: rooftops. Roof gardens have become ever more popular, especially in cities where land values and density are high. Food production is possible on an intensive green roof where the soil is deep enough to accommodate vegetables, like the Gary Comer Youth Center. These types of systems can be a bit expensive, especially compared to just having large boxes or pots of soil to grow in. A roof can be done by one group that takes care of the entire roof or can be split up and done as community garden plots.
Greenhouses can be an important addition to these urban agricultural systems, especially in northern climates where the growing season may be rather short. Adding a greenhouse component to these horizontal systems can allow for much higher production over a longer period of time. Greenhouses can even be operated in a more sustainable manner by using waste heat from a nearby building or industry to heat them.
Dr. Dickson Despommier, of Environmental Health Science at Columbia University makes a compelling argument for utilizing city skyscrapers for vertical farming. He notes that growing food indoors is already becoming commonplace with the techniques of hydroponics (growing plants not in soil, but with the roots in a nutrient rich water solution) as well as aeroponics (growing plants, not in soil but suspended with the roots exposed that are then sprayed with a nutrient-rich water solution).
DESPOMMIER’S IDEAS FOR SKYSCRAPER FARMS
Hydroponic and aeroponic greenhouses currently allow crops to be produced year-round with maximized yields because of ideal growing and ripening conditions. It can also be done without concern for outdoor environmental conditions such as soil, precipitation or temperature profiles and could even be supplied by gray water and powered by renewable technologies. By utilizing these existing technologies in dense, urban areas, a 30-story building covering one city block could produce 2,400 acres of a year.
Small scale vertical farming can be as simple as a few pots in window sills. There are some products that allow for easier vertical farming. Bohn & Viljoen Architects has designed a hydroponic system that can be hung in a window like a curtain.
NOT JUST FOR VEGGIES
The main reasons for urban agriculture are producing more food closer to home, food security and reducing the demand for food products generated by traditional agriculture systems. Therefore, urban agriculture isn’t just about growing produce, but can also include raising animals.
There has been a strong push for raising chickens in back yards, which is legal in Chicago and many other major cities. Producing much less waste and being less noisy than a dog, there are not many drawbacks to urban chickens. They can produce around an egg a day, which is more nutritious and delicious than store-bought eggs. They can also be fed table scraps, reducing feed cost as well as organic waste that would have to be shipped away.
Aquaculture is the farming of aquatic organisms, including fish, mollusks, crustaceans and aquatic plants. (‘Farming’ here implies some sort of intervention such as regular stocking, feeding, or protection from predators.) Both indoor systems in tanks, and outdoor systems in ponds can be used. Unlike most forms of livestock, aquaculture systems can be very compatible with nearby residential areas and provide an opportunity to treat organic domestic waste. In many countries, such as India, Thailand, China and Vietnam, human waste is used as a source of nutrients for aquaculture, which is then treated in the process; however, this practice needs to be done with extensive management in order to prevent disease. Tilapia and carp are the main fish used in aquaculture.
Dr. Noel Arrold took advantage of an existing disused rail tunnel in Sydney Australia and began growing mushrooms there. The cool, dark and damp space provides a perfect space for growing them, while reinvigorating this existing infrastructure.
Many cities have also started allowing the keeping of bees on rooftops. This greatly helps maintain a bee population within a city, which has many great environmental benefits like pollinating crops on green roofs and other urban farms. They also produce honey, which can be eaten or sold. There are many bee colonies in Chicago, including on City Hall, Chicago Cultural Center and the Marriott Hotel.
Urban farming is big news. You may not have heard too much about it but according to the UN Food and Agriculture Organization (UNFAO), urban agriculture is something that is practised by 800 million people worldwide, over one-tenth of the global population. So what exactly is it and how is it changing how we produce and distribute food?
What is urban farming?
Urban farming, or urban agriculture, can be described as the growing of plants and raising of animals in and around towns, cities and urban environments. Until recently, farming has been a largely rural activity. But the development of technology, together with a pressing need to find more sustainable ways of production and consumption, has led to the adaptation of farming techniques in more built up environments.
There are several different types of urban farms of varying scales that exist in different parts of the world, including commercial city farms, community gardens, community orchards, indoor vertical farms, hydroponic greenhouses, rooftop gardens, urban aquaponic farms (or fish farms), urban beehives and small-scale homestead farms. They produce a range of goods for local consumption or retail, such as grains, vegetables, fruit, meat, poultry, fish, herbs, honey and dairy products.
Urban farms can be small, medium or large-scale commercial enterprises, cooperatives run by community groups or residents, or even individual set ups. The farms have proliferated in both developed and developing countries in recent years, serving slightly different purposes in general in each. Farms in wealthier industrialised nations have largely been in response to the challenge to find more sustainable methods of agricultural production, along with moves towards more localized economies. In poorer countries, they have come about through multi-stakeholder efforts to combat food insecurity and hunger levels.
Why has urban farming become popular?
Urban farming has grown in popularity over the last 10–15 years. In the developing world, it has largely been driven by the rapid urbanization of developing regions. The urban population across the developing world has grown by around 500 million in the last decade and it is predicted that, by 2025, more than half of the developing world will live in urban areas. The main drivers of urban growth in these countries are high birth rates and an influx of rural people trying to escape poverty. Unlike countries where urbanization has been driven by industrialization, in low income areas it is often accompanied by high levels of poverty, unemployment and food insecurity. Urban farming has been seen as a way to combat all three of these problems.
In richer nations, the growth of urban agriculture has been in tandem with a return to localism, the growth of localized businesses, social entrepreneurialism and ethically-minded start ups. Social good and environmental sustainability are high on the agenda with new businesses, with one study finding that 90% of today’s CEOs and 88% of business students believe that sustainability is an important part of commercial success. Finding new and improved agricultural methods is an important area of sustainability. Studies have found that agriculture uses 38% of the world’s land area and is responsible for over 70% of global freshwater consumption. With more people concentrated in urban areas, farms can be more productive without using up the same level of resources. Warmer urban conditions are also conducive to the growing of crops.
Not all urban farming practices, however, are for a commercial profit. There are many such as community gardens and community orchards that are run by charities, community groups or resident cooperatives and exist for more social purposes such as sharing food, providing for poorer sections of the community, or bringing parts of the community together.
What are the impacts of urban farming?
Impact on businesses and the economy
Urban farming can have many positive effects on the local economy. As well as presenting green-fingered entrepreneurs with opportunities to start new local businesses, it also creates job opportunities for local people. Furthermore, farms can often provide local shops, supermarkets and restaurants with cheaper and fresher produce which has knock-on positive effects. One study has estimated that urban farms have the potential to provide around 10% of global vegetable crops, which could translate into big savings for local economies worldwide. Start up costs, however, are still high. Those involved in urban farming typically work longer than average hours, lose more food than rural farmers due to urban pests, and struggle to find skilled and experienced staff.
Impact on the environment
Urban farming has been championed as a way of improving agricultural environmental sustainability, but in truth it can have both positive and negative effects and it comes down to the way that farms operate and are regulated. Farms can provide a more efficient way of meeting local demand. If operated sustainably, they can reduce both the agricultural energy footprint (through eliminating the need to store and transport imported products) and the water footprint (through sustainable irrigation and water recycling). They can also transform wasteland into productive green space and stop it from becoming polluted. Vertical farms, which are set up inside multi-storey buildings and warehouses, also have the benefit of saving on space.
But studies have shown that urban farms can also increase energy and water use. Indoor farms, such as vertical farms, use energy-intensive artificial lighting and climate control systems. Many farms use the municipal water supply rather than a recycled water system for irrigation. There are also distinct health and safety risks with urban farming. Urban land can be contaminated with pollutants, while wastewater if not treated properly can contain human pathogens. This can compromise food safety if strict regulations are not in place.
Impact on communities
There are a number of positive social impacts associated with urban farming, such as:
improving food security and reducing poverty among the poorest by providing cheaper and more easily available food;
health benefits of providing affordable nutritious fruit, vegetables and organically produced meat;
greater social inclusion by providing local job opportunities and, in the case of community projects, bringing communities together;
educational opportunities for children, e.g. school trips to city farms and community gardens where pupils can learn more about where food comes from
However, urban farming has attracted some criticism in places such as Europe for becoming monopolized by the middle-classes and excluding lower income groups.
Who are the main players in urban farming?
Urban farming in Europe is not a new phenomenon. In fact, several countries encouraged the production of food in urban environments during both the First and Second World Wars in the 20th century. Today, start up urban agriculture enterprises are cropping up across the continent. At governmental level, individual governments have had limited involvement but the EU-funded Urban Agriculture Europe, a network of over 120 researchers, have been looking into ways in which urban farming can play a key role in future EU agricultural policy. Berlin-based start up InFarm has become the European urban farming leader with over 100 indoor and outdoor city farms in Germany, France and Switzerland. Among the largest urban farms in Europe are Space&Matter in the Netherlands, the Jones Food Company vertical farm in the UK, and the BIGH rooftop farm in Belgium.
There has been a growth in urban farming across the American continent in recent decades. In the US, policies and initiatives vary between states but projects ranging from vertical hydroponic enterprises to community gardens flourish across the country. A 2012 study by the United States Department of Agriculture (USDA) identified over 300 urban farms in the US. This includes one of the world’s largest urban farms located across nearly two acres in Chicago. In Canada, there has been more state-level involvement. Toronto in particular has been proactive, setting up a Food Policy Council which has drawn up a GrowTO Urban Agriculture Action Plan. In south and central America, where poverty and food insecurity are big issues in several countries, the UNFAO has been involved in kick-starting urban micro-gardens projects in countries including Bolivia, Colombia, Guatemala, Nicaragua and Venezuela.
Several Asian countries have invested significant amounts in urban farming technologies as a way of dealing with population growth and combating food insecurity. China, which has industrialized at a rapid pace in recent decades, has become a world leader in indoor vertical farming thanks to state investment. Similarly, Thailand has a community-supported agriculture initiative, led by the Thailand Environment Institute, that has helped create rooftop farms and indoor vertical farms across Bangkok. In India, another country that has urbanized at a pace, urban farming is now being seen as a sustainable food production method. Methods such as rooftop farming have taken off in cities such as Kerala.
The African continent has also seen wide-scale urbanization in recent years. Urban farming methods in the poorest countries have largely centred around setting up micro-gardening and community gardening projects, overseen by UNFAO, equipping urban locals with skills and resources to produce sustainable and feed the local community. Methods such as vertical farming are starting to take hold in some African countries. Johannesburg has hosted two Urban Agri Africa Summits to date, looking into possibilities of developing urban farming technologies across the continent.
Urban farming is unlikely to replace traditional agriculture any time soon but it will have a vital role to play in addressing challenges such as environmental sustainability and food insecurity in the coming years. As the world continues to urbanize and new technologies emerge, we can expect to see increasing governmental and inter-governmental involvement as urban farming becomes more mainstream. The key stakeholders will need to make sure that business models stay alert to environmental, social and economic challenges so that the farming of the future is a sustainable benefit for all.