The Tree You Choose Will Outlast Your Enthusiasm

There's a kind of small-garden makeover that photographs beautifully in year two and becomes a lawsuit by year seven. The tree is almost always the reason. Not because the designer chose badly in any dramatic sense (no one is planting Sequoiadendron giganteum in a terrace garden) but because they chose for the moment rather than for the decade, and the decade is what the client actually has to live with.

I've kept a running list for years. Not a wish list: a working list, revised after site visits and difficult conversations and one particularly memorable afternoon spent watching a council arborist explain to a horrified homeowner why the Prunus 'Kanzan' she'd loved for fifteen years now had to go. Roots under the patio. Canopy over the neighbour's kitchen extension. Nobody's fault, technically. Except the designer who specified it.

What follows is my current shortlist. It changes. But the principles behind it haven't.

Size Is Not the Problem. Shape Is.

The standard advice is to check the mature height and width and leave appropriate clearance. This is necessary but insufficient. A tree that tops out at eight metres with a spreading, low-branched crown behaves entirely differently from one that reaches the same height with a narrow fastigiate form: not just aesthetically, but in terms of light, root pressure, and the way it claims space over time.

Amelanchier lamarckii is the tree I specify more than any other in small gardens, and I'm aware that makes me sound conventional. I don't care. It earns its place on every axis: multi-season interest (the bronze spring emergence is better than the white flowers, which everyone mentions; the autumn colour is better than either, which almost no one mentions), a naturally elegant branching structure that requires almost no formative pruning, a root system that is genuinely well-behaved on most soils, and pollinator value that is real rather than theoretical. Early-season bees work those flowers hard. It won't shade out your vegetable patch. It won't heave your paving. It grows at a pace that lets clients feel the garden developing without waking up one morning to find the sky gone.

The pitfall: it sulks on thin chalk. If you're specifying on a chalk garden with a pH above 7.5, move on.

Cornus kousa var. chinensis is my second constant. Slower, which some clients resist until I explain that slower means you'll still be in control of it when they want to sell the house. The late-spring bracts are extraordinary: not the blowsy excess of ornamental cherries, but something more precise, more architectural. The strawberry-like fruits are edible and the birds know it. Autumn colour ranges from decent to spectacular depending on the summer. Again: well-mannered roots.

The pitfall: it needs reasonable drainage and resents late frosts catching those bracts. Plant it with some shelter and don't rush it into exposed positions.