If you’re yearning for an especially eco-friendly alternative to conventional mass-produced, flat-packed furniture, a designer duo in London might have just what you’re looking for. Sebastian Cox and Ninela Ivanova are growing chairs and lamps using fungus. The core of the biotech in the furniture is mycelium, the cotton candy-like, vegetative part of fungus. Cox and Ivanova say they drew inspiration from what they call an “ancient material relationship”: They mix the mycelium with woodchips from hazel and goat willow plants, then put the mixture in different molds. Over time, the mycelium spreads through the wood, and grows until it takes the shape of the container. The whole growing process is quick and easy to control. Designers decide when to halt the growth to achieve the ideal shape and texture. After drying the pieces, the mushroom-based products are strong, lightweight, and completely compostable—the designers say they have the feel of “velvet or leather.” Some people may not want to think of their furniture as compost. But the micro-organisms have huge potential in materials science and manufacturing, and a few companies in the US are also trying to develop a business around the stuff. A New York-based biomaterials company Ecovative grows clothes, furniture, and quickly-compostable packaging using mushrooms, and BioMason, a startup in North Carolina, claims to make stronger bricks using bacteria. Right now, Cox and Ivanova are in the prototyping phase—they are presenting the work for the first time at the London Design Festival 2017 this week—but they hope to scale up production in the future. In the meanwhile, if you want to buy mushroom furniture, you can try MycoWorks, though it’s not cheap—a stool goes for $300 and an armchair is $3,000. Or, for just $65, you can back Ecovative on Kickstarter and get your very own grow-it-yourself lamp kit.