Urban farmers are learning to grow food without soil or natural light

Hydroponics at work. Image: Getty.

Growing food in cities became popular in Europe and North America during and immediately after World War II. Urban farming provided citizens with food, at a time when resources were desperately scarce. In the decades that followed, parcels of land which had been given over to allotments and city farms were gradually taken up for urban development. But recently, there has been a renewed interest in urban farming – albeit for very different reasons than before.

As part of a recent research project investigating how urban farming is evolving across Europe, I found that in countries where growing food was embedded in the national culture, many people have started new food production projects. There was less uptake in countries such as Greece and Slovenia, where there was no tradition of urban farming. Yet a few community projects had recently been started in those places too.

Today’s urban farmers don’t just grow food to eat; they also see urban agriculture as a way of increasing the diversity of plants and animals in the city, bringing people from different backgrounds and age groups together, improving mental and physical health and regenerating derelict neighbourhoods.

Many new urban farming projects still struggle to find suitable green spaces. But people are finding inventive solutions; growing food in skips or on rooftops, on sites that are only temporarily free, or on raised beds in abandoned industrial yards. Growers are even using technologies such as hydroponics, aquaculture and aquaponics to make the most of unoccupied spaces.


Something fishy

Hydroponic systems were engineered as a highly space and resource efficient form of farming. Today, they represent a considerable source of industrially grown produce; one estimate suggests that, in 2016, the hydroponic vegetable market was worth about $6.9bn worldwide.

Hydroponics enable people to grow food without soil and natural light, using blocks of porous material where the plants’ roots grow, and artificial lighting such as low-energy LED. A study on lettuce production found that although hydroponic crops require significantly more energy than conventionally grown food, they also use less water and have considerably higher yields.

Growing hydroponic crops usually requires sophisticated technology, specialist skills and expensive equipment. But simplified versions can be affordable and easy to use.

They grow up so fast. Image: Mandy Zammit/Grow Up/author provided.

Hemmaodlat is an organisation based in Malmö, in a neighbourhood primarily occupied by low-income groups and immigrants. The area is densely built, and there’s no green space available to grow food locally. Plus, the Swedish summer is short and not always ideal for growing crops. Instead, the organisation aims to promote hydroponic systems among local communities, as a way to grow fresh food using low-cost equipment.

The Bristol Fish Project is a community-supported aquaponics farm, which breeds fish and uses the organic waste they produce to fertilise plants grown hydroponically. GrowUp is another aquaponics venture located in an East London warehouse – they grow food and farm fish using only artificial light. Similarly, Growing Underground is an enterprise that produces crops in tunnels, which were originally built as air raid shelters during World War II in London.

The next big thing?

The potential to grow food in small spaces, under any environmental conditions, are certainly big advantages in an urban context. But these technologies also mean that the time spent outdoors, weathering the natural cycles of the seasons, is lost. Also, hydroponic systems require nutrients that are often synthesised chemically – although organic nutrients are now becoming available. Many urban farmers grow their food following organic principles, partly because the excessive use of chemical fertilisers is damaging soil fertility and polluting groundwater.

To see whether these drawbacks would put urban growers off using hydroponic systems, my colleagues and I conducted a pilot study in Portsmouth. We installed small hydroponic units in two local community gardens, and interviewed volunteers and visitors to the gardens. Many of the people we spoke to were well informed about hydroponic technology, and knew that some of the vegetables sold in supermarkets today are produced with this system.

A simplified hydroponic frame in Portsmouth. Image: Silvio Caputo/University of Portsmouth/author provided.

Many were fascinated by the idea of growing food without soil within their community projects, but at the same time reluctant to consume the produce because of the chemical nutrients used. A few interviewees were also uncomfortable with the idea that the food was not grown naturally. We intend to repeat this experiment in the near future, to see how public opinion changes over time.

And while we don’t think hydroponic systems can replace the enjoyment that growing food in soil can offer, they can save water and produce safe food, either indoors or outdoors, in a world with increasingly scarce resources. Learning to use these new technologies, and integrating them into existing projects, can only help to grow even more sustainable food.

The ConversationAs with many technological advancements, it could be that a period of slow acceptance will be followed by rapid, widespread uptake. Perhaps the fact that IKEA is selling portable hydroponic units, while hydroponic cabinets are on the market as components of kitchen systems, is a sign that this technology is primed to enter mainstream use.

Silvio Caputo, Senior Lecturer, University of Portsmouth.

This article was originally published on The Conversation. Read the original article.

 
 
 
 

Treating towns as bastions of Brexit ignores the reasons for the referendum result – and how to address them

Newcastle: not all cities are booming. Image: Getty.

The EU Referendum result has often been characterised as a revolt of Britain’s “left-behind” towns and rural areas against the “metropolitan elite”. But this view diverts attention from the underlying issues which drove the Brexit vote – and ironically has diverted policy attention away from addressing them too.

It’s true that a number of big urban authorities, led by London, voted to stay. And overall people living in cities were less likely to vote leave than towns. Setting aside Scottish cities and towns, which both voted very strongly for remain, Leave polled 51 per cent of the vote in English and Welsh cities, compared to 56 per cent in local authorities that include towns. (Consistent data isn’t available below local authority level.)

Yet there is a lot of variation underlying this average across towns. In Boston, 75 per cent voted Leave, and in Hartlepool and Grimsby it was 70 per cent. But at the other end of the scale, there were a number of towns that voted to stay. For example, Leave polled at 49 per cent in Horsham and Harrogate, and 46 per cent in Windsor and Hitchin. In places such as Winchester, Leamington Spa and Bath, the Leave voted amounted to less than 42 per cent of the vote.

What drives this variation across towns? Data from the Centre for Cities’ recent report Talk of the Town shows economic outcomes were the biggest factor – with towns that voted Remain also having stronger economies.

For a start, pro-Remain towns generally have smaller shares of people who were either unemployed or claiming long-term benefit. (This is based on 2011 data, the latest available.)

Towns which voted Remain also had a higher share of jobs in high-skilled exporting businesses – an indication of how successful they have been at attracting and retaining high-paid job opportunities.

And both measures will have been influenced by the skills of the residents in each town: the higher the share of residents with a degree, the stronger the Remain vote.

So the Brexit vote was reflective of the varying economic outcomes for people in different parts of the country. Places which have responded well to changes in the national economy voted to Remain in the EU, and those that have been ‘left behind’ – be they towns or cities – were more likely to have voted to Leave.

This sends a clear message to politicians about the need to improve the economic outcomes of the people that live in these towns and cities. But the irony is that the fallout from the Brexit has left no room for domestic policy, and little progress has been made on addressing the problem that, in part, is likely to have been responsible for the referendum outcome in the first place.

Indeed, politicians of all stripes have seemed more concerned about jostling for position within their parties, than setting out ideas for domestic policy agenda. Most worryingly, progress on devolution – a crucial way of giving areas a greater political voice – has stalled.


There was talk earlier this year of Theresa May relaunching her premiership next summer focusing on domestic policy. One of her biggest concerns should be that so many cities perform below the national average on a range of measures, and so do not make the contribution that they should to the national economy.

But addressing this problem wouldn’t ignore towns – quite the opposite. What Talk of the Town shows is that the underperformance of a number of cities is bad not just for their residents or the national economy, but also for the residents in surrounding towns too. A poorly performing neighbouring city limits both the job opportunities open to its residents and impacts on nearby towns’ ability to attract-in business investment and create higher paid jobs.

This isn’t the only factor – as the last chart above suggests, addressing poor skills should be central to any serious domestic policy agenda. But place has an influence on economic outcomes for people too, and policy needs recognise that different places play different roles. It also needs to reflect the importance of the relationships between places to improve the access that people across the country have to job opportunities and higher wages.

The Brexit vote didn’t result from a split between cities and towns. And if we are to address the reasons for it, we need to better understand the relationship between them, rather than seeing them as opposing entities.

Paul Swinney is head of policy & research at the Centre for Cities, on whose blog this article first appeared.

Read the Centre’s Talk of the Town report to find out more about the relationship between cities and towns, and what this means for policy.