Start with how the garden is actually used

Most family gardens are asked to do three contradictory things at once: be a playground, be productive, and be somewhere an adult can sit with a mug of tea. Trying to satisfy all three in one tidy space is where the trouble starts. Before you buy a single bag of bark chippings, spend a fortnight watching how your children use the garden. You will usually notice patterns: bikes and balls drift to one stretch, digging and den-building happen in another, and everybody cuts the same line between the back door and the shed.

Once you can read those patterns, divide the plot into loose zones rather than strict rooms. A hard-wearing play zone, a growing zone with raised beds, and a sitting area close to the house where you can supervise without standing over anyone. The zones can overlap, but each needs its own surface and its own rules — and that alone saves a great many trampled seedlings.

Lay the ground so falls are forgiving

Grass is the default surface and still the best value for general running about, but it will wear to bare mud beneath a swing or along a scooter route. Play to its strengths in the open middle of the garden, and use something tougher under and around fixed equipment. Whichever surface you choose, check the depth recommendations that come with the play equipment itself, and top up loose materials each spring.

• Hard-wearing grass: overseed worn patches with a ryegrass-dominant mix each autumn and keep a small bag of seed in the shed for running repairs.
• Bark chippings: affordable, soft underfoot and good for a play area, but rake it back into place regularly and top up annually as it composts down.
• Rubber play tiles or a rubber crumb surface: the most durable option under a climbing frame or slide, though it costs more and needs a firm, level base underneath.
• Play sand and pea gravel: excellent for digging and pouring, but keep a lid or cover on sand to stop cats treating it as a litter tray.

A cheap and very effective trick is to place a paving slab path along the route children run most often. Muddy shortcuts turn into permanent trenches otherwise, and a firm dry path keeps the rest of the lawn intact.

Make the boundaries secure without making them bleak

Aim for a boundary that stops a child leaving and slows an intruder, without turning the garden into a stockade. For a fence bordering a road, pavement or open ground, 1.8 metres is the usual sensible height; between neighbouring gardens, 1.2 metres is plenty. Walk the whole perimeter yourself and look for the things children find: gaps under panels, a wobbly gate latch, and the compost bin that makes a handy step.

Any gate should be self-closing and fitted with a latch a small child cannot reach or work out. If you have a pond, be honest about it. Either fence it properly, fit a rigid mesh cover, or convert it to a pebble-filled bubble fountain until the children are older. A water butt needs a lockable lid as well as a tap, and it should sit on a stable base rather than a wobbly stack of bricks.

Protect your sightlines

The single most useful design test for a family garden is this: stand at the kitchen sink, then at the back door, and check that you can see every play area from at least one of them. If you cannot, something needs moving.

• Keep tall shrubs, trees and sheds to the perimeter, and keep the middle of the garden low — roughly knee height or below.
• Use low hedging, ornamental grasses and groundcover in the centre rather than dense evergreens that block the view.
• Avoid placing a playhouse, tunnel or willow den where it becomes a blind spot; angle openings towards the house instead.
• Add a couple of solar or low-voltage lights along the main route so the garden stays usable on autumn evenings.

A bench or bistro set positioned where you can see the whole plot is worth more than any amount of clever planting. Supervision works best when the supervising adult actually wants to sit there.

Choose plants that survive children

Plant thickly and in bold blocks rather than fiddly borders, because dense planting suppresses weeds and shrugs off the occasional football. Tough, forgiving perennials do the heavy lifting: hardy geraniums, lady's mantle, heuchera, sedum, catmint, ferns and lamium all recover quickly from being sat on.

Steer clear of thorny shrubs in areas children use, and be cautious with plants that are toxic if eaten or that have irritant sap — foxgloves, laburnum, monkshood and euphorbia are the usual ones to keep out of reach. Then add the fun: herbs such as mint, thyme and lemon balm for smell, tall grasses that rustle, and edible crops like strawberries, peas, cherry tomatoes and currants. Give each child a pot or a raised bed of their own, and let them decide what goes in it.

Sort the water, tools and storage

Family gardens fail on the small practical details. A lidded sandpit, a lockable store for tools and chemicals, a hose reel that does not become a trip hazard, and a waterproof box for balls and scooters will do more for the garden than another border. Site a trampoline away from fences, trees and hard paving, and check the clearance guidance before you sink or assemble it. Keep a small basket by the back door for wet gloves and muddy boots, and the whole space becomes easier to live with.