Urban agriculture: The edible city

How worried should we be about food security? How pressing a concern will it be for city planners and designers?

It’s a huge problem right now, let alone what might be the case in 10, 20, 30 years. According to official figures, there’s close to a billion people who are hungry in the world today. If we look at more realistic measures of hunger — in terms of calories that people need to live an active and physical life — somewhere between 1.5 and 2 billion people are hungry or in extreme food insecurity right now. Then you have another 2 billion suffering micronutrient deficiency and another 2 billion overweight and obese, which is a different form of malnutrition. So it’s pretty clear that the food system is very dysfunctional and unequal and producing a whole range of very perverse and problematic outcomes.

In terms of city design, the climate predictions are extremely concerning. The latest Intergovernmental Panel on Climate Change (IPCC) report suggests that absent some very serious action on climate change, we’re on track for 4°C of warming, and the impacts of that on our food and agricultural systems will be absolutely catastrophic. We’re beginning to see that right now with the appalling summer of bushfires that we’ve experienced in Australia. And COVID-19 certainly highlights the importance of urban food systems. So it’s something that needs to be very high up our social, political and economic priorities. Because if we can’t feed ourselves, then everything else becomes moot. The big shift in human history over the last 100 years has been from an agrarian, rural population to an urban one and that trend shows no sign of slowing. In a highly uncertain climate future, that means we need to be planning for food in cities.

How far could cities feed themselves? Are there limits to urban agriculture?

Urban agriculture already plays a significant role. According to the Food and Agriculture Organization of the United Nations, an estimated 800 million people are involved today, producing about 20% of the world’s food. And they are doing so in conditions that are marginal, with precarious land tenure and very little support from governments. So if urban agriculture were to be taken seriously, then its potential could be considerable.

Part of the answer to this question depends on what we are going to be eating. What does a sustainable diet look like? The EAT-Lancet Commission report (2019) talks about a diet for planetary health as one that is increasingly plant-based. That’s where urban agriculture really comes into its own, because cities aren’t so appropriate for livestock agriculture. We’re not going to have cattle herds in cities or large-scale pig or poultry farms. But if new technologies are embraced, cities can go quite a long way towards feeding themselves with fresh and healthy produce, particularly vegetables, but also fruit and poultry. A University of Melbourne research project recently found that Melbourne could satisfy about 40% of its own food requirements from the productive capacity in the greater metropolitan area, and about 80% of its fruit and vegetable requirements.

If urban agriculture is done well, it can be enormously productive. We’re in discussions with an agritech company called BioFilta that uses a form of urban agriculture technology called wicking beds. It’s climate-smart urban agriculture that conserves water — there’s a reservoir of water at the bottom of a raised bed, so you water from the bottom not the top. Biofilta estimates, based on extensive experience with their advanced wicking bed technology, that growers can produce about 30kg of fresh produce per year in one square metre. To translate that to broad-acre farming, you’re talking about 300 tonnes per hectare, which is a huge yield. In Australia, even irrigated wheat in best-performing conditions only yields about eight to ten tonnes per hectare.

Do the figures for Melbourne take into account that 4°C increase, or would that completely change everything?

Broad-acre agriculture in Australia — and worldwide — will be massively impacted by a 4°C temperature rise. In his 2007 book, Six Degrees, Mark Lynas said, “None of the continent of Australia — except perhaps the extreme north and Tasmania — will be able to support significant crop production in the four-degree world because of heatwaves and declining rainfall.” Climate-controlled agriculture in cities using technologies such as wicking beds — with appropriate shading to protect plants on days of extreme heat — would still be productive. But to be frank, I think none of us really want to see what a 4°C warmer world looks like and we should do everything in our power to keep the rise under 1.5°C, as recommended by the IPCC.

Will some places feed themselves better than others? Or will we just have to change our eating habits?

Food growing definitely varies from place to place. Personally, I am not an advocate of locavorism — the idea that we should just be eating what we can grow within our immediate geographical location. Part of the joy of food is being able to experience cuisines from other cultures, and I think it really connects us as a global community. I would hope that there would still continue to be trade, including of food. Having said that, it is a pretty flagrant and excessive use of energy and resources to fly produce halfway round the world when we can produce it in our own region, simply because it’s cheaper.

There will continue to be a very necessary and important role for agriculture in the more rural sense, in the way that we have farmed for thousands of years — certainly if we’re going to continue to eat livestock. I am not of the view that we should all become vegetarian or vegan, but we need to move to diets that are more balanced in terms of having a greater proportion of vegetables, fruit and wholegrains. Grains need extensive landscapes in order to grow effectively, so we’re not going to be doing that in cities.

There are different ideas of urban agriculture, with ultra-modern tower farms at one end of the scale, and allotments or community gardens at the other. What do you think the future looks like?

It’s quite a burgeoning and diverse field with lots of different production methodologies and technologies. One of my organization’s projects is the Melbourne Food Hub, a post-industrial site about 10km from the CBD of Melbourne. Right now there’s a beekeeper, and a craft brewer who’s making wild-yeast-fermented craft beer. There is an aquaponics start-up, which produces protein in the form of fish, with the fish waste becoming nutrients for plants grown in a stratum above the fish tank. They’re growing microgreens, which is a very highly nutritious, high-value product that they sell to restaurants in the city.

Just coming onto the site now are two women who grow seasonal mushrooms in shipping containers — again a very nutritious, high-value crop. Then we have above-ground urban farming with wicking beds.

There’s a food waste composting business called Reground, which collects the spent coffee from cafes and restaurants and makes that freely available to backyard and community gardeners for their composting. Then there’s a weekly farmers’ market, with about 35 regional and rural producers who come from around the city. And we’re in talks with a Sydney-based organization that turned two disused bowling greens into a market garden, growing food very productively and selling it to restaurants.

It’s high-value produce, but it’s also urban agritourism. There are birthday parties, weddings, workshops, educational opportunities — multiple layers of social enterprise to support a viable farming business. In one small site of about an acre, all these different organizations are working together. It ’s like an exercise in placemaking — repurposing degraded, rundown, post-industrial wasteland and making it productive, welcoming and a centre of enterprise and employment. We hope it’s a glimpse of what a better food system would look like in an urban context.

What is your vision for sustainable urban food networks, and how far are we from that today?

My vision would be all of those things, and lots more, just being commonplace and happening everywhere, and an urban future in which it’s just normal to see productive food pretty much in every street, in every neighbourhood, where we have urban forests, allotments, community gardens, verge gardens, market gardens, school gardens.

For me, food has always been fundamentally a question of social justice and equity. My background is in law and I got interested in food systems around 2000 when I was working in Guatemala in the field of human rights. It was not so much about sustainability, but food and agriculture as a source of conflict and tension and violence.

There is something in international law called the Human Right to Adequate Food. It’s part of the Universal Declaration on Human Rights, and it means that access to food should not be a matter of your status in society, your income, your gender, your ethnicity. Everybody should be able to access good, healthy food, at all times, simply by virtue of being human. I think we need to design our cities and food systems with that goal in mind. We’re a very, very long way away from that right now.

From a sustainability perspective, in terms of the food system contributing to soil fertility, to the restoration of water catchment areas, habitats and biodiversity, and to human health and wellbeing — again, we’re a long way from that. We need a huge paradigm shift in agriculture generally. Over the last 100 years or so, agriculture has been seen as almost a war waged by humanity against nature in order to extract our food from the soil and from ecosystems. We’ve done huge, huge destruction in that process.

How might current planning or design decisions support or hinder food security in the future? How can we make sure we’re not creating problems for the future?

Recognition of urban agriculture in planning frameworks is a really important first step. This is a critical planning issue for us in Melbourne and for many places around the world, because for many decades, we’ve had a development dynamic that doesn’t really value agricultural land or food. Since the start of the 20th century, Melbourne has lost probably three-quarters of its productive land capacity, but even with what’s remaining, we can still at our current population of 4.5 million satisfy 80% of our horticultural requirements. If we keep losing land, that 40% will drop to about 18% by the time we reach 7.5 million people in the 2040s. So it’s critical for the city to start protecting that remaining farmland and also put in place support mechanisms for farmers.

In Melbourne, there are so many blocks that just sit for months and sometimes years behind a cyclone fence, until the developer decides it’s time to build. But there’s no reason why they couldn’t be given a discount on rates or an incentive if they made the land available for urban farming. Those are the kinds of policy frameworks that need to be thought about.

Also, realizing that it’s not simply about growing food, but supporting livelihoods, encouraging local networks and doing comprehensive inventories of land and asset mapping at the municipal or regional level. That would include built form, like rooftops and post-industrial sites. If there are old factories that are lying vacant, could they be turned into centres of urban agritech? One of the roles for planners and designers is to have these conversations to understand what kind of infrastructure, land requirements, technologies and methodologies are needed to plan intelligently for a range of possible futures.

The challenges are enormous and it can be quite daunting, but it’s a great space to work in, full of dynamic, energetic, creative people who are getting stuck in and making a big difference in their own lives and in the lives of communities around them. It gives me a lot of hope.

Dr Nick Rose is executive director of Sustain: The Australian Food Network, a lecturer in food studies at the William Angliss Institute, and a global adviser to the UN Global Compact Cities Programme