Choosing the Right Spot

A wildlife pond does not need to be large. Even a sunken washing-up bowl will draw in frogs, damselflies and birds if it is placed well, and position matters more than size. Aim for a spot that receives sun for at least half the day: amphibians and dragonflies seek out warmth, and flowering marginals need light to bloom.

Keep away from trees and large shrubs. Fallen leaves rot down and turn the water stagnant, hungry roots can puncture a liner, and heavy shade suppresses the plants that keep a pond healthy. Avoid the lowest corner of the garden if it collects runoff from paths or beds, since that water arrives carrying nutrients and any weedkiller or fertiliser used nearby. And think about where you will enjoy it — a spot visible from the kitchen window means you notice the first frog of spring.

Digging Varied Depths

Mark out a shape with a rope or hose laid on the grass. Irregular outlines look more natural than circles, and gently sloping edges beat steep sides for wildlife. Then vary the depth:

• A central area 60–80cm deep, where frogs and newts can overwinter below the frost line.
• One or two underwater shelves 20–30cm down for marginal plants and shelter.
• A shallow beach at one end, sloping gradually into the water so hedgehogs and fledgling birds can drink and climb out.

Check the surrounding ground is level with a spirit level and a plank, so the water sits evenly and the liner does not show along one edge. Stack the turf you lift upside down nearby to make a habitat pile.

Lining and Filling

For a dug pond, a butyl or EPDM liner is the durable choice, laid over an underlay of geotextile, old carpet or soft sand. Measure generously: the longest width and length, plus twice the maximum depth, plus 60cm of overlap all round. Tuck the surplus into a shallow trench around the rim and cover it with soil, turf or paving.

Fill with rainwater from a butt wherever possible. Tap water contains chlorine and dissolved nutrients that can trigger an algae bloom before plants have settled in. If you must use tap water, let it stand for a day or two and accept that the water may go green for a few weeks. Leave the pond to settle for a week before planting, and resist the urge to stock it: wildlife finds new water remarkably quickly on its own.

Planting with Native Species

Plants do the heavy lifting in a wildlife pond. They oxygenate the water, shade out algae and give insects somewhere to perch and lay eggs. Choose British natives where you can:

• Oxygenators such as hornwort and water milfoil, which live entirely underwater.
• Marginals such as marsh marigold, water forget-me-not, water mint and lesser spearwort around the edges.
• Floating plants like frogbit, offering shade and landing pads for damselflies.

Plant in aquatic baskets lined with hessian and filled with soil-based aquatic compost, then top with gravel to stop it clouding the water. Steer clear of invasive species such as New Zealand pygmyweed, parrot's feather and water fern — they spread fast and are illegal to release into the wild. Leave one stretch of bare, sunny margin, and add a log or a few flat stones so frogs and insects have somewhere to bask.

Safety and Small Spaces

If young children use the garden, keep the water 30cm deep or less, or fit a rigid mesh cover flush with the surface until they are older. Supervise at all times and check fencing and gates.

For wildlife, the priority is escape. A gently sloping beach, a ramp of stones or a piece of roughened wood leaning into the water gives frogs, hedgehogs and insects a way out. Avoid steep, slippery sides, and never add goldfish, which eat frogspawn and tadpoles.

Small Water Features and Upkeep

No room to dig? A half barrel with no drainage holes, a glazed pot, an old butler sink or even a large bucket will work. Sink it so the rim sits just above soil level, add a couple of oxygenators and a marginal, and leave a stone inside as an escape route.

Maintenance is light. Top up with rainwater in summer, scoop out fallen leaves in autumn, and pull out blanket weed by hand rather than using chemicals. Do not empty and scrub the pond — the silt and decaying leaves at the bottom are home to larvae and overwintering newts.