The War on the Fever Tree

I went down to the Waterfront to look at the new Cape Town EDITION hotel. Its brickwork has attracted plenty of attention. What stopped me in my tracks was the planting: Fever Trees. Again!

At the edge of the Atlantic, in a historic working harbour, another prominent new landscape was being furnished with the same visual shorthand. Green trunks. Fine foliage. An instantly recognisable suggestion of Lowveld savannah and KZN's northeast corner.

Once you start noticing them, the repetition becomes difficult to ignore. I see it around the CBD, along the Heerengracht and in new landscapes in Century City. Different projects, different settings, remarkably similar answers.

This is my war on the fever tree. The tree itself is innocent. The habit deserves a fight.

A national border is not a planting brief

The fever tree, Vachellia xanthophloea, can be a magnificent tree. Its bark and branching are distinctive. In the right setting, its light canopy is part of its appeal. It is also associated with wet ground and seasonal water in the summer-rainfall parts of eastern and southern Africa. It is not a tree native to Cape Town’s Atlantic shoreline.

That does not automatically disqualify it from a Cape Town landscape. It does, however, expose the weakness of using “South African indigenous” as though it settles the question of local suitability.

A tree from the country’s north-east does not become ecologically local to the south-western Cape because both places sit inside the same national boundary. Nor does a tree from a comparable climate abroad become unsuitable solely because it comes from outside it.

There is a glaring irony here. South Africa’s political boundaries were shaped by colonial conquest and political settlement, not drawn around climates, biomes or the natural ranges of trees. Yet those inherited boundaries are sometimes treated as though they confer ecological belonging. A tree passes the national-origin test, and the questions about its actual relationship to this place seem to fall away.

This is where environmental concern becomes performative: when certainty about what belongs outruns knowledge of where a tree comes from, what conditions it evolved in, or what it contributes to the place where it is being planted. Knowing that a species occurs naturally somewhere in South Africa is the beginning of that enquiry. It is not the conclusion.

Climate compatibility matters. So do soils, water, wind, habitat relationships and the risk of escape into surrounding ecosystems. A national label cannot do all that work. If we are serious about local ecology, we should be precise about what “local” means. If we are designing an urban landscape, we should be equally precise about what we need it to do.

The landscape is part of the place

The recent argument over oak planting in Stellenbosch brings this into focus. The Plant an Oak project is responding to the loss of trees in the historic centre, including the damage caused by polyphagous shot hole borer. Yet some of the online responses I encountered seemed to stop at a single objection: why plant anything that is not indigenous?

It's because the trees are part of the place.

People admire Stellenbosch’s historic streets as though the buildings alone produce that experience. They do not. The canopy, the scale of the avenues, the summer shade and the seasonal opening of the sky help make those streets what they are. Replacing that living structure is an act of urban design as well as horticulture.

Why recognise that history in a building, then refuse to recognise it in a landscape? If you would lament the demolition of a historic building but object to the continuation of its surrounding tree canopy solely because the trees are exotic, your defence of heritage has become strangely selective. The urban fabric does not stop at the façade. It includes the living elements that frame it, shade it and give the street its proportions and seasonal rhythm.

An introduced tree can become part of a cultural landscape without becoming botanically indigenous. Those are different forms of belonging. We should be capable of recognising both without confusing them.

Heritage is not a licence to ignore ecological harm. Research from Stellenbosch University has documented invasion by some oak species along waterways and at the urban edge. Pest vulnerability also demands care in choosing replacements. Calling something an oak does not make it safe, any more than calling something indigenous makes it suitable.

Those are arguments for discriminating choices. They are not a reason to pretend the cultural landscape has no value. A historic street and a habitat-restoration site need different botanical briefs. Both deserve ecological intelligence. Neither is served by performative outrage or eco-washing; they need sound solutions for each context.

When a distinctive tree becomes the default

My frustration with fever trees is that a distinctive species has become, in too many places I encounter, an unremarkable and monocultural answer. The green bark is doing an extraordinary amount of work. It supplies an immediately legible idea of “African savannah landscape," as if Cape Town desperately needs to reaffirm it, everywhere.

It does not need to borrow the visual vocabulary of the Lowveld at every opportunity to prove it. Cape Town is not Mbombela. Mbombela is not Cape Town. Both are part of this nation and continent, and both deserve landscapes attentive to their own conditions and character.

Nor is recognisability enough to justify a public-space tree. Where the brief is shelter from summer sun, what matters is the shade reaching the pavement and the people using it. In some of the fever-tree plantings I encounter, the canopy feels too thin for that task. Dappled light can be beautiful. Whether it is sufficient from December to March is both a design and human comfort question.

An open canopy is not evidence of no cooling. Nevertheless, mature crown density, available rooting space, seasonal leaf cover, irrigation and the placement of thorn-bearing branches all deserve more attention than a handsome silhouette on a presentation board.

A tree should earn its place through more than its ability to look recognisably African. Plus, our rich continent has plenty of non-savannah biomes.

There is no single, compulsory Cape aesthetic either. New landscapes should be allowed to surprise us. But surprise requires more than repeating the same tree outside a different building. Broaden the palette

This is not a demand to replace fever trees everywhere with oaks. That would reproduce the same failure under a different canopy. Even among the trees traditionally grouped as acacias, there is a much wider range of architectures and characters to consider.

Beyond them lies a substantial horticultural palette, including locally indigenous trees and responsibly selected introduced species. Each still needs to be assessed for the site.

The question is why so little of that possibility becomes visible in the places we build.

Nursery availability and production economics are real constraints. Designers may also carry responsibility for survival, maintenance and client expectations, therefore familiar choices can be defensible. However, if familiarity repeatedly determines the specification, how will demand for alternatives ever develop? This is creativity giving way to what is proven and to what is easy.

I want clients to ask for a reasoned planting palette and for designers to be educators. I want landscape practices to make room for experimentation, and emerging designers to have opportunities to demonstrate it. Seasonal character, canopy structure, human comfort and a sense of place should be central to that conversation.

There are two habits worth challenging here: repetitive planting presented as placemaking, and the blanket suspicion of anything introduced. I would call botanical xenophobia and by that, I mean judging a tree’s worth by foreign origin alone. Evidence of invasion or ecological damage is an entirely different matter and must be taken seriously.

The landscaping standard should demand the following: protect local ecosystems, account for future conditions, create useful shade and mitigate climate-change impacts, respect the history of a place and give people landscapes worth inhabiting.

Keep the fever tree in the palette. Stop letting it become the palette.