Mews gardens are generous in character and stingy in space. A cobbled yard, a slim border, a wall you share with three neighbours — there is room for a tree, but only a well-behaved one. The trick is not to keep a tree small by hacking at it, but to choose the right plant and then prune it at the right moment, with the right cut. Get those two things right and a tree will stay shapely, healthy and generous with blossom for decades.

Start with the calendar, not the secateurs

Most small-garden pruning goes wrong because it happens at the wrong time of year, not because the cut itself was poor. The simplest guide is the flowering season of the tree in front of you.

Trees that flower in spring on last year's growth — ornamental cherries, plums, amelanchier, magnolia, cercis — carry their buds through the winter. Prune them in winter and you are cutting off next spring's display. Wait until immediately after flowering, usually late May to midsummer, and the tree has already done its work for the year.

Trees that flower on the current season's growth, such as heptacodium and many late-flowering shrubs grown as standards, can be pruned in late winter or early March while dormant. This encourages strong new shoots that will bloom in late summer.

There are also two disease-driven exceptions worth memorising. Prunus — cherries and plums especially — should be pruned in July or August, when silver leaf spores are least active; winter cuts on these are an open invitation. Maples and birches bleed heavily if cut in late winter or early spring, so prune them in late summer or early autumn instead. A little sap loss is rarely fatal, but it is unsightly and stresses a young tree unnecessarily.

The four cuts that matter in a tight space

In a courtyard you rarely need to shape a tree dramatically. You need to remove, thin and gently reduce. Four cuts cover almost everything:

• Dead, damaged and diseased wood — remove at any time of year, back to clean, healthy growth.
• Crossing and rubbing branches — take out the weaker of the two so wounds cannot develop.
• A thinning cut — remove a whole branch back to its point of origin. This lets light and air into the centre without stimulating lots of regrowth.
• A reduction cut — shorten a branch back to a strong side shoot. Use this sparingly for containment, never as routine topping.

Make every cut just outside the branch bark ridge, leaving the collar intact — that is the tree's own healing tissue. Avoid flush cuts and long stubs, and skip wound paints entirely; they trap moisture and do more harm than good. As a rule, never remove more than a quarter of the canopy in a single year. If a tree needs serious reshaping, spread the work across three winters or, better, three post-flowering summers.

Pruning the mews favourites, tree by tree

• Amelanchier: needs almost nothing. Thin lightly after flowering in June, removing the oldest stems at the base every few years.
• Japanese maple and paperbark maple: prune only to remove dead or awkward growth, in late summer. Keep cuts small; maples heal slowly.
• Ornamental cherry, including narrow columnar forms: July to August only, after flowering has finished, and lightly.
• Crab apple: prune in late winter for structure, accepting the loss of a few blossom buds, or in May if the display matters more than the shape.
• Cornus kousa: late winter, before growth starts, removing low shoots to lift the crown.
• Cercis and magnolia: after flowering, in midsummer, and only if genuinely necessary. Both resent heavy pruning.

Keeping a young tree small by design

The easiest way to keep a tree manageable is to start early. A young whip can be trained to a clear stem of 1.8 to 2 metres over three or four years, so you can walk beneath it and park a bicycle without ducking. Remove lower side shoots gradually, no more than a third of the trunk's height in any one year.

Choose multi-stemmed forms where you want presence without bulk — they read as larger than they are and cope well with restricted root runs. In containers, prune to balance top growth with root volume, and go easy on high-nitrogen feeds, which produce soft, floppy growth that needs cutting back again within months.

Boundaries, tools and the neighbours

Mews living is close living. Keep branches at least a metre clear of a shared wall or fence, partly to avoid shading a neighbour's kitchen window and partly because sticky sap over a parked car sours friendships quickly. In most gardens there is no automatic right to light, but courtesy is cheaper than a dispute.

Before any significant work, check whether your mews sits in a conservation area or whether the tree carries a Tree Preservation Order — both require council consent, and the fines for ignoring them are real.

Finally, invest in three tools: sharp bypass secateurs, a pair of loppers and a pruning saw for anything thicker than your thumb. Clean the blades with methylated spirits between trees, avoid pruning in hard frost, and mulch and water well afterwards. Do that, and your courtyard tree will stay a pleasure rather than a problem.