This summer, more than 25 architectural practices have designed treehouses for bonsai trees. The results are on display in Oxford Square Gardens, Connaught Village, as part of the Museum of Architecture’s Bonsai Treehouses exhibition.
It sounds playful, and it is. There are miniature villages, spiral staircases, suspended platforms, bug houses and structures inspired by fungi, pine cones and Japanese traditions.
But look closer and some very grown-up questions begin to emerge.
What happens when architects have to respond precisely to what is already there? Can buildings make space for other forms of life? What turns a collection of structures into a community? And what might London learn from an architecture of patience and care?
A bonsai is not a naturally miniature species. It is a tree shaped gradually over many years, sometimes across generations, through observation, patience and continuing care.
That immediately changes the architectural brief.
Each practice has had to respond to a particular living tree, with its own trunk, branches, roots and irregularities. The architecture must adapt to the tree, rather than expecting the tree to accommodate the architecture.
There is something refreshing about that reversal.
London is full of existing things: buildings, streets, trees, infrastructure, communities and memories. Yet development conversations can still begin with a strangely blank piece of paper.
At miniature scale, several practices have explored another approach.
Design International used photogrammetry to map the bark of a 40-year-old hawthorn before designing five tiny dwellings fitted precisely to different sections of its trunk.
Mamou-Mani Architects and Fab.Pub scanned the branches, forks and voids of their bonsai to find natural points of support. Their miniature village was shaped by the tree itself.
Arup Architecture suspended timber platforms from branches without allowing the structure to rest on the tree.
Different solutions, but a shared question: how can we build with what exists rather than simply over it?
For a city wrestling with retrofit, reuse, heritage and the protection of mature trees, that is not a small question.
What does a city look like from another point of view?
When buildings are designed for a tree rather than a conventional human client, familiar assumptions begin to loosen.
White Arkitekter’s Circular Bughouse is not intended for people at all. Made from timber and clay, it provides a seasonal resting place for bees and insects before gradually disassembling as autumn arrives.
Haptic Architects’ The Commons makes room for birds, insects and people. Hyper Space Architects has created a micro-ecosystem using salvaged timber, plants and living mycelium.
These are tiny speculative structures, not proposals for London’s next neighbourhood. But the question behind them is useful: who counts as an inhabitant of the city?
London is a human habitat, but it is also an ecosystem. Birds nest in buildings. Insects depend on connected habitats.
Fungi and microorganisms sustain soils and trees. Parks, gardens, railway edges, cemeteries, balconies and roofs form part of a much larger urban network.
Foster + Partners’ contribution, The Forest Unseen, makes one of these hidden systems visible. Inspired by the underground fungal networks associated with tree roots, its woven structures explore the relationships that allow a forest to function.
Cities work through hidden relationships too. The places we see depend upon infrastructure, maintenance, logistics, care and countless connections that are often invisible until they fail.
Sometimes changing the scale helps us see the system.
One of the exhibition’s most explicitly urban contributions comes from Stride Treglown.
The Gathering Grove: Togetherness in Miniature clusters dozens of individual treehouses around a central town hall.
Its argument is simple: places become richer when buildings are arranged in relationship to one another.
Again, the scale is tiny. The issue is not.
London’s housing debate is necessarily dominated by numbers. How many homes can be built? Where will they go? At what density? How quickly can they be delivered?
But a collection of homes is not automatically a neighbourhood.
The spaces between buildings matter. So do places to meet, play, learn, shop, sit and participate in civic life.
Tibbalds Planning and Urban Design explores a similar idea with Kizuna, conceived as a miniature community hub with a garden, water feature, gathering spaces and a shared perch.
These are playful projects, but their preoccupations are familiar. How do individual spaces become shared places?
Where does private life meet community life? What physical conditions help relationships form?
London asks these questions at the scale of millions of people. Sometimes it is useful to see them asked around a single tree.
Perhaps the biggest lesson from bonsai is not about scale at all. It is about time.
Cities tend to celebrate architecture at the moment of completion. The scaffolding comes down. The photographs are taken. The ribbon is cut.
Bonsai works differently.
Its value comes from continuing attention. Watering, pruning, wiring and responding to change are not maintenance tasks that follow the creative work. They are the work.
London is very good at discussing what should be built. We are often less enthusiastic about discussing how places will be cared for over the next 10, 20 or 50 years.
Yet everyday city life depends enormously on stewardship. A park is not simply designed; it is maintained. A housing estate is not finished when the homes are occupied; it must be repaired and managed. A public square needs cleaning, planting, lighting and care.
The change of scale in Bonsai Treehouses is revealing. Freed from the usual expectations of a major building project, architects are asking questions about coexistence, adaptability, community, materials and long-term care.
The scale may be very different, but the questions are connected. How do architects respond to constraints? How do they work with what already exists? What relationships are hidden beneath the finished object? And what can a tiny experiment reveal about making places at a much larger scale?
The treehouses may be tiny, but the questions are not.
For London Society members who want to look more closely, we have secured a private, members-only behind-the-scenes tour of the Bonsai Treehouses exhibition. It will be a chance to explore the ideas behind the miniature structures and hear more about how the architects responded to the unusual challenge of designing around a living tree.
If you cannot join our private tour, London Society members and supporters can use the code LondonSocietyBonsai for £10 off tickets to visit the exhibition at other times. On the page to select ticket types choose “use ticket access code” and input code to unlock this ticket option.
Bonsai Treehouses, presented by the Museum of Architecture, runs at Oxford Square Gardens in Connaught Village from 4 July to 31 August 2026.
