The delivery man arrives back at the farm, his produce drop-offs for the day complete. He’s greeted by ecstatic barking from his three dogs, one of which leaps into his arms, licking his face enthusiastically.
It’s a familiar scene from any farm, anywhere in the world. But this delivery man didn’t drive through muddy fields or down country roads to get here. He freewheeled his bicycle down the blue-striped spiralling entrance of an underground car park.
This is La Caverne, the only subterranean agricultural operation in Paris. It is housed within 9,000 sq m of a disused multistorey parking facility beneath a social housing complex. Since 2017, Jean-Noël Gertz, a thermal engineer and founder of agricultural start-up Cycloponics has used this space to grow mushrooms and endives and deliver them to the organic shops of the city’s inner north.
Gertz shows me around the facility, which winds deeper and deeper. One level down, a conveyor belt runs across several numbered parking bays, along which staff separate endives from their gnarly roots and pack them into crates for delivery. Endives, grown entirely without sunlight, are a perfect crop for a below-ground venture like this. Reportedly discovered by a Belgian farmer who tried to hide chicory roots from the taxman in his cellar only to find they grew delicious, tender leaves while they were down there, endives are now the fourth most popular vegetable in France.
As we descend even further, Gertz has the straightforward air of someone who thinks running a farm out of an underground car park is a perfectly normal thing to do. He says he doesn’t mind spending most of his time below ground. “We have a lot of space here and we walk a lot, we’re all in very good health,” he says.
Odd as it seems in the heart of the city, this kind of agriculture may soon become widespread as demand for organic, locally produced food grows and car use declines. Underground farms have sprung up in other major capitals such as London and New York.
This particular one runs three storeys deep below a public housing complex in Porte de La Chapelle. Built in the autocentric 1970s, by the time Cycloponics moved in there were just 40 vehicles left. The area has the double the poverty rate of the Paris average, and 30% of residents under 25. Owning a car is simply no longer an option for many people.
Indeed, across Paris, 58% of working households do not own a car. As mayor Anne Hidalgo continues to discourage driving and encourage public transport, the city is looking for new uses for these vast subterranean spaces.
Since 2016, the town hall’s Pariculteurs programme has offered up spaces like this – as well as rooftops and courtyards – to businesses willing to turn them green. Businesses like Cycloponics can bid for these spaces in a public call. Parisculteurs estimates that by 2022, there will be 1,240 tonnes of fruit, vegetables, mushrooms, herbs and 1.3m plants grown in Paris every year.
Saffa Riffat, the president of the World Society of Sustainable Energy Technologies, says that if the world is going to feed 9 billion people by 2050 agriculture will have to move underground. Riffat is leading a project at Nottingham University on how to convert the 12.5 sq km of abandoned mines in the UK into farms.
“With limited land, the only idea is to grow food underground and leave the land above for people,” he says.
He gives the example of China, where vast swathes of land are too contaminated to farm and many people are being sent to the big cities to live.
“People are moving from the countryside to the city so there’s [fewer and fewer] farmers to grow food. So, we have to move the overall infrastructure of growing food from the countryside to cities,” he says.
Clapham, south London, is home to Growing Underground, a massive hydroponic operation in a second world war air raid shelter. While La Caverne specialises in vegetables that don’t require sunlight, Growing Underground uses LED lighting to grow herbs, microgreens and salad leaves – something that’s only become possible in recent years with advances in technology, says co-founder Steven Dring. Eight to ten years ago, the lighting available would have made the tunnel too hot to grow anything down there, he says.
Growing Underground supplies restaurants and supermarkets with 15 different product lines and has deals with Tesco, Marks & Spencer and Ocado, among others.
“Anything that’s local in provenance and sustainable is just going to pay a larger and larger role in people’s purchasing decisions,” Dring says.
Back at La Caverne, Gertz takes me to see the mushrooms. Neat rectangular bales are suspended from the ceiling in rows, small clusters of mushrooms sprouting out of each. Steam pours out of overhead pipes and the floor is under a centimetre of water in parts. “We have to recreate autumn in here,” he says.
Unlike the familiar carpark sound of footsteps echoing in concrete, the air here smells like a fusty forest floor. It is thicker, damper and warmer than the crisp early winter day above ground.
Controlling the temperature year-round is one of the major advantages of underground farming.
champignons de Paris in artificially autumnal conditions. Photograph: Kasia Wandycz/Paris Match via Getty Images
The disadvantages, Gertz says, involve frequent water leaks and having to haul the farm’s waste up to ground level to dispose of it – not to mention the Herculean effort required to clean the polluted space to the standards required for organic certification.
If hyperlocal city produce seems like the ultimate 21st century demand, there is actually a surprising precedent for growing mushrooms under the streets of Paris. Throughout the 19th century, farmers grew champignons de Paris – button mushrooms – in the abandoned quarries below the city. Stones taken from these underground caverns gave the Hausmann buildings of the capital their distinctive rose-grey hue, and left behind a perfect environment for the fungus to thrive.
The mushrooms were pushed out of the city that gave them their name with the construction of the Métro at the turn of the 20th century. Now, the popularity of the Métro and the decline in car use is what’s bringing them back.
In 2020, with the opening of Cycloponics’ second Paris location, and alongside their shiitake and oyster brethren, champignons de Paris will be grown within city limits once more, 90 years after they disappeared. La Caverne already produces 100-200kg of mushrooms a day, selling to places like Le Producteur Local, an organic supermarket and non-profit cooperative of 45 producers that stocks meat, cheese and vegetables all grown within 150km.
“You have to realise that most of what we eat in Paris is cultivated, raised or produced 600km from where we live,” says director Julien Roudil, pointing out that much of what a Parisian household regularly consumes is in fact readily available within just 60km.
Although he’s a champion of local produce, Roudil says Paris will probably never be able to feed itself entirely, no matter how many rooftops or carparks are converted into farms. The popularity of locally grown produce already outstrips the local land available for farming, he says, and there’s not enough space available in Paris to supplement that at a reasonable price.
Dring is more optimistic about the prospects of greater London becoming self-sufficient, whether by growing on rooftops, on barges on the Thames or in bunkers. “All these different technologies will be complementary to each other. I think London will certainly be sufficient within 100 miles,” he says.
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