From a container wafts the sweetly pungent odor of coffee grounds which, far from being discarded as waste, are being lucratively recycled to produce oyster mushrooms.
Grounds, which Parisian brasseries throw out daily by the ton, are perfect for the job, and a snapshot of a fast-growing urban agricultural trend.
The mulch of grounds is mixed with cardboard and wood chips and shoved into lengths of plastic with pieces of mushroom culture.
They are then hung vertically in a dark space and left to incubate for a fortnight.
“We are reproducing undergrowth subsoil conditions. The temperature and humidity are comparable,” explains Arnaud Ulrich, co-founder of UpCycle-La boite à champignons (mushroom box), based in the Paris suburb of Saint-Nom-la-Breteche.