Beneath Belgium’s city streets, something is growing in the dark. Moist, cool cellars have become hip spots for urban mushroom farms. A group of entrepreneurs in the city of Brussels is making a far-fetched fungi idea feasible. They’re learning that another popular trend above ground creates magic down below.
Belgium is known for its ale-making tradition. But brewing beer generates waste from fermented grains. The result is an excess of spent organic material that can be used again—this time, to cultivate exotic mushrooms. Quentin Declerck and his business partners are putting that waste back to work and seeing success from their efforts. They’re producing healthy, sought-after food by harnessing the good stuff in organic brewery waste.
Hadrien Velge and Sevan Holemans founded “Le Champignon de Bruxelles” in 2014. First, they tried growing varieties of Shiitake, Maitake, and Nameko mushrooms using coffee grounds for the substrate. A substrate is the material that an organism draws its nutrients from. Soil is the most common substrate for most farming projects. Coffee was a good initial substrate idea. But it turns out that mushrooms flourish better on soft, mealy, mushy grains.
“It did not work out well with coffee, so we teamed up with the Cantillon brewery down the road,” Declerck says. “In cities, the beer waste would normally be thrown away.”
The underground cellars of the famed Abattoir meat market in Brussels’ Anderlecht neighborhood are an ideal setting for urban farming. The 32,000-square-foot space below the market stays cool, dark, and moist—just the environment that fungi love. In that setting, this urban farm also never drops below 52° Fahrenheit, so freezing the crop is not a concern. Packets of spore-imbued substrate line row upon row of shelves. The farm is burgeoning with produce—generating about five tons (that’s 10,000 pounds!) of the fungal delicacies every month!
What do locals think about the underground urban mushroom initiative? Benjamin Gaugué is a cook who thinks the farms are ingenious. “They sell good products and promote sustainability,” says Gaugué. He appreciates the ecological wisdom of the waste-to-food project.
And what was once trash keeps paying its potential forward—one more step. After the mushroom harvest, the substrate can be used again in yet another capacity. Local farmers use the mushroom-exhausted material as organic fertilizer. So the cycle continues—used grain becomes substrate for organic mushrooms before heading back into the soil to feed and sprout new grains.
For everything there is a season, and a time for every matter under heaven: a time to be born, and a time to die; a time to plant, and a time to pluck up what is planted. — Ecclesiastes 3:1-2