This Abandoned Parking Garage in Paris Is Now a Mushroom Farm

If you've never heard of "cave gardening" before, don't worry. You're not the only one. I had no idea what it was until I watched an episode of the BBC's Follow the Food show and was introduced to the agricultural miracles taking place beneath the streets of Paris. Now I'm utterly fascinated by what could be a glorious future for urban food production.

Cycloponics is the name of an agricultural startup that runs a farm called La Caverne, located in an abandoned underground parking garage. Deep down in that empty concrete space, urban farmers produce organic mushrooms – between 220 and 440 pounds (100-200 kilograms) per day and in numerous varieties, from shiitakes to oyster mushrooms to white button mushrooms – as well as endive, France's fourth most popular vegetable (and grows in complete darkness), and microgreens, which require LED lights. 

A 2019 writeup in the Guardian describes the space as having a fusty, forest smell: "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,' [the guide] says."

Why is a parking garage available for farming, you might wonder? Back in the 1970s, it was mandated that every new residential building in Paris have two parking spots per apartment, but as car ownership has declined, due in part to mayor Anne Hidalgo's ongoing efforts to discourage driving and incentivize public transit, these spaces are now often empty. Underground farming, however, gives them new and improved purpose.

Jean-Noël Gertz, thermal engineer and founder/CEO of Cycloponics, told Treehugger that the farm was started in December 2017. The mushrooms are grown in straw bales. "First the straw is sterilized, then incubated with mycelium. We then do the fruiting." The harvest is transported by cargo bike to a food cooperative that distributes it to retailers. La Caverne's website says it aims for emissions-free transportation, and that only 10% of remote deliveries are made by car, soon to be electric. 

The act of growing food beneath a city's streets has numerous benefits. Most obviously it shortens the distance food has to travel from farm to plate. La Caverne prides itself in short turnaround times, allowing customers to serve up mushrooms picked that same day. More than that, La Caverne wants to build relationships between eaters and farmers. Translated from the website:

"We want to see the emergence of a model of urban agriculture that is both productive and virtuous, help to rethink the city of tomorrow, imagine new ways of producing, restore the image of farmers, often misunderstood, create new local jobs, revitalize neighborhoods, and finally to offer urban residents quality local production."

La Caverne is located in the neighborhood of Porte de la Chapelle, beneath a social housing complex with over 300 units. The Guardian says, "The area has the double the poverty rate of the Paris average, and 30% of residents under 25." The farm offers produce to residents at preferential rates, as well as educational workshops, and strives to hire locally. "We want to actively participate in the transition of the neighborhoods where we operate," its website reads. "In addition, all our [harvest] surpluses are sent to [food banks] or to restaurants. Sharing is at the heart of our values."

More than three years in, La Caverne is thriving. When asked if this model could be copied elsewhere in an effort to boost food security, Gertz told Treehugger, "We already replicated it in Bordeaux. Next step is Lyon, and we will open two other spots in Paris next year."

It's exciting to see such an innovative model taking off, especially when it takes advantage of abandoned spaces and makes them productive in the most practical of ways – feeding people. The world can always use more cave gardens!