Start with the space, not the plant

Walk your boundary before you buy anything. Note how much sun it gets, whether the soil sits wet through winter, and how close you can plant without causing trouble with a fence or a neighbour. As a general rule, leave at least 60cm between a new hedge and any boundary, and remember that a hedge clipped to 1.8m will usually want 60–90cm of width. In a courtyard of twenty square metres, that is a serious commitment — so it pays to choose something that grows no more than 20–30cm a year.

Think in decades, too. A hedge is a long-term planting, and the mistakes that hurt most in small gardens are the ones you cannot undo: a screen that ends up two metres deep, or a plant that needs cutting three times a year to stay neat. Growth rate, eventual width and clipping frequency matter far more here than they do in a large garden.

Compact evergreens for year-round screening

Evergreens give you privacy in January as well as July, but many traditional hedging plants are far too vigorous for a tight plot. Avoid leylandii, cherry laurel and large-leaved photinia unless you genuinely have the space and the patience. These are better behaved:

• Yew (Taxus baccata) — slow, dense and shade-tolerant, adding roughly 20–30cm a year once established. Clip once in late summer. All parts are toxic, so site it away from grazing pets and curious toddlers.
• Box (Buxus sempervirens) — the classic low hedge, ideal at 30–60cm. Keep plants well spaced and air moving through them, as box blight and box moth thrive in tight, damp, clipped blocks.
• Japanese holly (Ilex crenata) — looks like box but shrugs off blight. Happier in light shade than in full sun on dry soils.
• Pittosporum tenuifolium — small glossy leaves, responds well to clipping, and copes with wind and salt. Give it shelter in cold inland gardens.
• Euonymus fortunei — tough, low and colourful, useful for a 60cm boundary or the gap beneath a window.
• Bay (Laurus nobilis) — a working hedge as well as a screen; keep it clipped to about 1.5m and you need never buy a bay leaf again.

For a quick low hedge, plant box or Japanese holly 30–45cm apart. For yew, 45–60cm is plenty and gives each plant room to knit together without crowding.

Deciduous hedges with seasonal interest

Deciduous hedging drops its leaves in winter, so it is never a complete screen — but bare twigs still break up a sightline, and you gain colour, wildlife and often a lower price per metre.

• Hornbeam (Carpinus betulus) — holds coppery leaves well into winter if you clip it in late summer, and copes with heavy clay.
• Beech (Fagus sylvatica) — a similar look with a lighter, more golden tone; prefers free-draining soil and keeps its leaves if you leave the autumn trim alone.
• Field maple (Acer campestre) — butter-yellow autumn colour and a manageable 1.5–2m boundary height.
• Hazel (Corylus avellana) — late-winter catkins and nuts for the birds; coppices well if it outgrows its spot.
• Spindle (Euonymus europaeus) — vivid pink and orange autumn fruits, best used as part of a short mixed run rather than a whole hedge.

In a small garden, one species almost always looks better than a jumble. If you want a mixed native hedge, limit yourself to three species and repeat them in blocks rather than dotting them about.

Hedges that earn their keep

A hedge takes up ground, so make it work. Holly (Ilex aquifolium) is one of the best small-garden evergreens for wildlife: plant a female variety with a male nearby for berries that feed thrushes and blackbirds through the hardest weeks. Clipped yew and hornbeam give dense nesting cover, while a run of hazel or field maple supports moths and their caterpillars. If you can spare one wider section, a native mix of hawthorn, blackthorn and hazel will do more for wildlife than any clipped evergreen, though it needs an annual cut to stay tidy — and keep it away from the washing line.

Planting and keeping it in check

Bare-root hedging goes in between late autumn and early spring, whenever the ground is neither frozen nor waterlogged. Container-grown plants can be planted at almost any time if you water them diligently through the first summer. Prepare a strip at least 45cm wide, fork in well-rotted organic matter, and set plants at the spacing above. Water weekly for the first two seasons, and more often in dry spells.

Pruning is where small gardens are won or lost:

• Clip evergreens in late summer, once nesting is over and the year's growth has finished.
• Trim deciduous hedges in late summer too, if you want beech and hornbeam to hold their leaves.
• Cut to a slight batter — narrower at the top than the bottom — so light reaches the base and it does not go bare.
• Never take more than a third of the growth in one go, and keep your shears sharp; ragged cuts invite disease.

Choosing for your spot

If you want privacy all year and the boundary sits in shade, yew is hard to beat. For a low, formal edge in sun or light shade, choose box or Japanese holly. If the soil is heavy clay and you would rather have autumn colour than winter screening, hornbeam is the answer. If wildlife is the priority and the boundary is generous, a short native mix will repay you. And if you simply want a herb hedge by the kitchen door, bay clipped to chest height will do the job in a single metre of border.

Whichever you choose, plant it slightly further from the boundary than you first intended. You will thank yourself in ten years.