The archive · Small Business & Money · Technical decision · 1820–1900
Paris cave growers turn abandoned quarries into a mushroom capital
From 1820, Parisians farmed champignons de Paris in abandoned limestone quarries, where stable darkness, temperature and humidity grew mushrooms year-round.
Paris cave mushroom growers
What it had to solve
Limestone mining left miles of empty tunnels under Paris, and the mushroom Louis XIV had made fashionable at Versailles needed controlled conditions to fruit reliably. Growers needed a way to produce it at scale.
How it works
For centuries Paris mined the limestone its buildings stand on, leaving vast networks of empty quarries under the city; in the 18th century parts became the catacombs. Mushrooms were already a delicacy — Louis XIV had made the white button variety fashionable by growing it at Versailles — but fruiting year-round demanded controlled temperature and humidity.
In 1820 farmers began growing mushrooms in the quarries, and the method took off. Rows of nutrient-rich horse manure were laid in the caves, where constant temperature and humidity and the darkness encouraged growth in any season; covering the compost with ground limestone kept the mushrooms from absorbing excess water and gave them a nutty, almost mineral taste.
The industry made Paris the reference for the button mushroom — the name champignons de Paris outlived the city's production. Around 250 growers worked the quarries in the late 19th century, beds filled even the tunnels of the catacombs, and in the 20th century the technique spread to Belgium and the Netherlands, where the Riemst–Maastricht quarries became major producers.
Why it lands
- The caves delivered what the crop needed — stable temperature, humidity and darkness — as free infrastructure the growers did not build.
- Horse manure was abundant in a horse-powered city, so the substrate was a waste stream with no transport cost.
- Ground limestone improved the product itself, adding flavour and preventing waterlogging that ruined shelf life.
- A farm under the city could sell to Paris's own market without cold chains, a natural fit for a perishable crop.
What it did
Champignons de Paris became a world-famous product: around 250 growers worked Paris quarries in the late 19th century, beds once filled even the catacombs, and the technique later spread to Belgium and the Netherlands.
What you can take
Read a wasted asset for what it already supplies — Paris's quarries gave stable temperature, darkness and humidity for free. The cheapest factory is often the one nobody built.
Since then
Urban growth and the Paris metro began pushing growers out of the capital in the early 1900s, though about 50 quarries under the suburbs were still farming in the 1970s. Cheaper mushrooms from industrial sheds in the Netherlands, Poland and later China took most of the market. By 2021 only five traditional producers remained around Paris: Shoua-moua Vang's Les Alouettes, the largest cave farm at 1.5 hectares, still sold everything it produced — 2.5 to 3 tonnes a day at 3.20 euros a kilo wholesale — against France's 90,000 tonnes a year.
Sources
- Deep underground, Paris mushroom growers struggle to preserve heritage
- Photoessay | Underground Mushroom Farms
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