Soil erosion 'greatest threat to planet'

Growing from foam
Soil-free farms could help take some of the pressure off traditional agricultural systems while we instigate a much needed step-change in farming policy.


By the time you’ve finished reading this paragraph, the world will have lost another football pitch of soil. At current rates of erosion, 90 percent of our planet’s soil could be gone by 2050, according to the UN’s Food and Agriculture Organisation.

Natural soil erosion is being accelerated by deforestation, mining, urban sprawl and - ironically - the intensive agriculture that simply couldn’t function without it.

The increasingly extreme heatwaves, droughts, floods and storms that come with climate breakdown only make matters worse - damaging crops, ruining livelihoods and sending food prices soaring around the world.

Radical solution

At the same time, our population is growing - estimated to reach 10 billion people by 2050, when the UN fears we’ll be eking an existence out of just 10 percent of the soil we have now. Without soil, we face starvation.

At the University of Sheffield, we’re pioneering a radical solution that could buy us some time. Our new Institute for Sustainable Food has launched a soil-free urban farm, where scientists are growing food from foam.

Harry Wright - a PhD student at the Grantham Centre for Sustainable Futures - has developed specialist foams that chemically, physically and biologically resemble soil.

Together with Jacob Nickles, N8 Knowledge Exchange Associate at the University of Sheffield Institute for Sustainable Food, Harry has used a network of pipes, nutrient solutions and controlled growing environments, scientists are growing everything from salad to tomatoes in an abandoned school in Sheffield.

Community participation

We’ve found that crops planted in the polyurethane foams grow two to ten times faster than plants grown in soil.

The potential of this low-cost system has already been demonstrated with an initiative - led by Grantham Centre Director Professor Tony Ryan in collaboration with Professor Duncan Cameron - to install hydroponics systems made from used mattresses at a refugee camp in Jordan, where planting straight into the soil isn’t allowed.

In Sheffield, we’re putting our research into practice again to provide fresh fruit and vegetables for our local community, as well as training for local unemployed or low-skilled workers and an educational environment for schools.

Our hope is to replicate this model across the globe and optimise it for local conditions to produce cheap, healthy food using fewer resources.

These soil-free farms could help take some of the pressure off traditional agricultural systems - but they’re no excuse to carry on as usual. Foam alone will never feed the world.

We urgently need a new approach to farming that protects and restores our soils, eliminates waste, enhances the natural world and gives everyone their fair share of nutritious food.

Policy changes

To get there requires science and innovation - but, most importantly, a step-change in policy and public attitudes.

The Institute for Sustainable Food will produce groundbreaking research to form an evidence base for a better agricultural system, bringing together experts across every discipline, from politics and computer science, to geography and medicine.

But with a crisis unfolding beneath our feet, it’s not enough to publish academic papers and discuss theories with our peers.

Opening our urban farm to the public sets the tone for our new institute. We’ll be learning from our community about what food they want to see us grow and asking how they’d like to be involved.

It’s time for scientists like me to step out of the lab and work with farmers, politicians and local people to put our research into practice. We won’t solve the soil crisis without getting our hands dirty.

This Author 

Professor Duncan Cameron is director of the University of Sheffield’s new Institute for Sustainable Food.