Creating a Wildlife Pond in a Small Garden

A Pond the Size of a Doorstep

Walk any lane in Britain in early spring and you will hear it before you see it: the low, knocking chuckle of frogs gathering to spawn. Most of them are not travelling far. Frogs, smooth newts and a whole cast of insects will happily colonise water no bigger than a washing-up bowl, provided it holds water through the summer and has somewhere to climb out. That is the quiet miracle of a mini pond. You do not need a half-acre, a digger or a pond liner the size of a duvet. A corner of paving, a shady patio edge or the strip beside a shed will do very nicely.

In return you get frogspawn in March, damselflies hovering in July, and birds dropping in for a drink and a bath all year round. A small pond is one of the kindest things you can do for your garden's wildlife, and one of the cheapest.

Choosing the Right Spot

Find a place that gets sun for at least four to six hours a day. Sunshine warms the water, which encourages the algae, insects and plant growth that everything else depends on. Deep shade tends to produce a cold, lifeless pond.

The ground needs to be reasonably level, because anything that is not will tip and spill. Avoid the lowest point of the garden, where rainwater will flood the pond and wash in soil, and avoid spots directly beneath trees, which will fill it with leaves.

• Keep it away from where children play unsupervised.
• Leave a gap in nearby fencing so hedgehogs can reach it — they drown in steep-sided water.
• If you have very young children, consider a raised container with a sturdy mesh cover.

Building a Pond Without Digging

The simplest method is to sink a container. A half-barrel, a large glazed pot, an old Belfast sink, a stone trough or even a sturdy trug will all work. For frogs to breed you want a depth of about 40 to 60 centimetres in the middle, with shallower shelves around the edge. But do not be put off by a shallower container — even 20 centimetres of water will bring in insects, and insects bring in everything else.

Waterproof containers with drainage holes need lining. Use a piece of butyl liner or a heavy-duty pond liner, pressed into the shape of the tub and folded neatly at the rim. Fill it with rainwater from a water butt if you possibly can. Tap water contains nutrients and chlorine that feed algae, so if you must use it, let it stand for a few days first.

Then leave it. Seriously — leave it. Do not add fish, however tempting. Fish eat tadpoles, newt larvae and the insects you are trying to attract, and they turn clear water cloudy.

Planting a Miniature Marsh

Plants shade the water, starve algae of light and give creatures somewhere to hide and lay eggs. Aim for roughly half the surface covered. Good British natives include:

• Water forget-me-not — soft blue flowers and excellent cover for tadpoles.
• Marsh marigold — brilliant yellow cups in early spring, loved by bees.
• Water mint — aromatic, with lilac flowers that hum with insects.
• Lesser spearwort — a delicate buttercup for shallow water.
• Hornwort or curled pondweed — submerged oxygenators that keep the water clear.

Plant into baskets of aquatic compost topped with gravel, or simply wedge them on the shelves. Never introduce invasive species such as floating pennywort, water fern or New Zealand pygmyweed; these can escape from a tiny pond and smother a whole waterway. Around the edge, let the grass grow a little longer and add a few native perennials, so amphibians have damp cover to retreat into.

Making It Safe and Welcoming

Steep sides are the biggest danger in a small pond, for wildlife as much as for anyone else. Give frogs, newts and the occasional hedgehog a way out:

• Place a gentle ramp of stones, brick or roughened wood at one end, angled from the water to dry land.
• Leave a shallow pebble beach where birds can stand and bathe.
• Float a small piece of cork or a few twigs as an emergency ladder for insects.

Add a few stones and broken terracotta pots at the bottom for hiding places. And keep the water topped up in dry spells with rainwater, ideally in the cool of the evening.

Looking After It Through the Year

Resist the urge to tidy. A pond that looks slightly scruffy in autumn is a pond that is working properly. In late summer, clear a little duckweed or blanketweed by hand if it takes over, and leave it on the edge overnight so any trapped creatures can crawl back.

In autumn, net out fallen leaves before they rot, because decaying leaves feed algae and starve the water of oxygen. Between October and February, cut back dead plant growth but leave the cuttings beside the pond for a few days.

Come the first warm week of spring, sit quietly nearby with a cup of tea. You will likely see the surface dimple with insects, a frog's eyes just breaking the water, and a blackbird waiting its turn. A patch of water no larger than a doormat, and the whole garden is suddenly busier.