Habitat 25

Habitat 25 demonstrates how cities can become productive ecologies by integrating food cultivation directly into their spatial and cultural infrastructure. Over just 30 m², the installation produces hundreds of kilos of Grifola Frondosa (maitake), a rare and nutrient-rich mushroom. Compared to traditional beef production, the same nutritional output would require over 100 times more land. By relocating food production to urban environments, we release vast areas in the countryside for rewilding, biodiversity and ecosystem restoration.

The mushroom chamber is constructed as a ‘circular hack’ of the Danish Architecture Center’s own modular exhibition system, wrapped in translucent membranes and climate-controlled to support continuous, zero-waste production. Using upcycled organic waste such as coffee grounds and sawdust as growing substrate, the installation illustrates how architecture can transform waste into nourishment and embody the future of urban metabolism.

At the core of Habitat 25 is the rare maitake mushroom, sometimes called “the unicorn of the forest” for its unique ecological needs. Naturally growing only in ancient oak forests, it is both a culinary delicacy and a bioindicator of high-quality, mature ecosystems. In Japanese, maitake means “dancing mushroom,” referring to the joy of its discovery and its historical value, once worth its weight in silver. In Denmark, its decline mirrors the ongoing erosion of deep natural time and complex forest habitats.

Through its cultivation in an artificial urban microclimate, the installation does not just reproduce a rare species, it also reframes the cultural, economic, and ecological narratives around food. Habitat 25 becomes a living parable about scarcity, symbiosis, and regenerative imagination. It invites visitors to ask what kind of nature we value, and what kind of cities we want to inhabit in a time of accelerating crisis.

Inspired in part by John B. Calhoun’s “Universe 25” mouse experiments, where utopian conditions led to social collapse, Habitat 25 reflects on the systemic traps of modern urbanism. Calhoun’s closed and uniform environments became metaphors for cities that fail to adapt socially or ecologically. In contrast, this project proposes a living, responsive, and modular habitat where circularity, care, and complexity are central design principles.

The installation also challenges the binary between urban and rural, architecture and agriculture. It questions why urban mushroom farms like the now closed Bygaard urban farm in Copenhagen, initiated by Lasse Antoni Carlsen, remain excluded from agricultural subsidies, despite offering climate-friendly, high-efficiency food. Habitat 25 is a call for regulatory and imaginative shifts, a stage where desirable futures become visible, and where architecture reclaims its role as a hopeful actor in the Anthropocene.