If your garden is little more than a courtyard behind a terraced house, the temptation is to treat it as a corridor to the bins. Resist that. A modest plot of four by five metres can feel generous if you plan it around how you actually live outdoors, rather than around a vague idea of what a garden ought to look like.

Begin with a brutally honest survey

Before you buy a single pot, spend twenty minutes with a tape measure and a notebook. Note the width and depth, but also what direction the space faces, where the sun lands at three in the afternoon in June, where neighbours overlook you, and where the drain covers sit.

Then write down the three things you most want from the space. Realistically, most compact urban gardens have to do two or three jobs at once — somewhere to eat, somewhere to sit quietly for ten minutes, somewhere to dry the washing. Once you know the jobs, you can decide which one gets the best spot and which gets whatever is left. A north-facing yard will never be a sun-trap, so design it as a cool, green, shade-loving space instead of fighting the aspect.

Push the planting up the walls

When floor area is scarce, the vertical plane is your biggest asset. A fence or house wall four or five metres long gives you more usable growing surface than the entire lawn.

• Climbers with proper support. Fix stainless steel tension wires or slatted timber trellis to the fence, then plant star jasmine for evergreen coverage and scent, or a late-flowering clematis for colour without bulk.
• Wall-mounted planters. Three or four rectangular planters at eye level lift herbs and trailing plants clear of your feet. Water them with a drip line on a timer, because a hose reel and good intentions are not a maintenance plan.
• Green screens. Trellis clad in evergreen climbers adds privacy without stealing a metre of ground.

Keep heavier planting at the boundaries and lighter planting near the house to avoid a hemmed-in feeling.

Build in seating rather than buying it

Freestanding furniture eats space and rarely fits neatly into an awkward corner. Built-in seating is the single most effective change you can make.

A bench or L-shaped run along one fence line can be built from the same brick or block as the wall, topped with smooth timber battens or a stone slab. Raise the seat to about 450mm and make the depth 450–500mm. Add lift-up lids and the void underneath becomes storage for cushions, tools and the children's football.

If you would rather not build, a simple rendered blockwork plinth with a composite deck board on top does the job and costs less than a decent garden sofa. Buy or make a couple of weatherproof cushions and the whole thing doubles as an outdoor room.

Treat the floor as a room, not a gap

Cheap, uneven paving makes a small garden feel scruffy and narrows it visually. Choose one material and stick to it: porcelain pavers with a 10mm joint, riven sandstone, or decking laid on adjustable pedestals so water drains away freely.

Run the paving in the same direction as the longest dimension to stretch the eye. If there is a step, keep it shallow and wide rather than steep and narrow, and use the level change to separate a seating area from a planted one. A single large pot at the junction of two materials does more for the composition than half a dozen small ones scattered about.

Leave a planting gap of at least 300mm along the fence for soil and roots. Plants crammed hard against a wall will struggle, however carefully you water them.

Light it properly and use it after dark

Lighting is the difference between a garden you look at and a garden you use. It also makes a small space feel deeper, because you can light the far boundary and leave the middle in shadow.

• Warm white, always. Choose 2,700K fittings; anything cooler turns a leafy courtyard into a supermarket car park.
• Uplight the boundary. One or two spike lights tucked into planting and aimed up a fence or small tree cast shadows that add depth and hide the true size of the plot.
• Layer the levels. Festoon lights on a catenary wire between house and fence give soft overhead light for eating, while a low-level step light keeps the route safe.
• Keep it weatherproof. Everything outdoors should be rated at least IP44, and IP65 for anything low or set into the ground. Use a timer or a smart plug so it comes on without you thinking about it.

Plant for year-round structure

A small garden has nowhere to hide in winter, so structure matters more than flower count. Start with two or three evergreen shrubs — a clipped box or yew ball, a compact mahonia, a small acer in a pot — and build perennials around them.

Hakonechloa, Japanese anemones, hardy geraniums and salvias all cope well with UK conditions and tolerate the shade that comes with enclosed plots. If you want bamboo for screening, choose a clumping variety or fit a root barrier, or you will spend the next decade digging it out.

Fill gaps with spring bulbs, which cost very little and give you colour before the perennials have woken up. Mulch with a 50mm layer of bark or garden compost in spring to cut watering and keep weeds down. A small plot managed like this needs perhaps half an hour a week in summer — and repays you every evening you sit out there.