Creating a Wildlife Pond in a Small Country Garden

A Small Pond, A Great Deal of Life

Few garden features repay a weekend's work as generously as a wildlife pond. Even a modest one, no more than a couple of metres across, becomes a magnet for frogs, toads, newts, dragonflies and a whole cast of beetles, bugs and water snails within a season or two. On a summer evening, bats will drop down to drink from it. Hedgehogs will come for a quiet sup at the edges. In a small country garden, hemmed in by hedges and a bit of rough grass, a pond is less a decorative extra than a piece of rural heritage brought back into working order.

The good news is that the wildlife pond is the opposite of a koi pond. No filters, no pumps, no fish, no chemicals. The muddier and more natural it looks, the better it works.

Choosing the Right Spot

Sunlight drives everything in a pond — the algae, the plants, the insects, the warmth that frogspawn and tadpoles need to develop. Aim for at least five or six hours of direct sun a day, ideally with dappled shade at one end during the hottest part of the afternoon, which helps keep the water from overheating and the blanket weed from taking over.

Avoid the obvious temptations as well as the obvious pitfalls:

• Keep clear of mature trees. Fallen leaves rot down and load the water with nutrients, and roots make digging a misery.
• Steer clear of low frost pockets at the bottom of a slope, where cold air pools and ice lingers.
• Do not site it where garden run-off drains in, or where a downpipe discharges. You want rainwater, but not a torrent of silt and nutrients.
• Think about the view from the kitchen window. A pond you can watch while the kettle boils will be a pond you notice, and notice means looked after.

Digging, Lining and Filling

An informal, curvy shape suits wildlife better than a rectangle, chiefly because it gives more edge, and edge is where the life is. Dig with a gentle profile rather than a bucket shape. A good template for a small garden pond is:

• A central depth of 60–75cm, deep enough that frogs and newts can overwinter in the mud without the whole thing freezing solid.
• One or two planting shelves at 20–30cm for marginal plants.
• A shallow, gradual "beach" on one side, no steeper than a gentle slope, so that hedgehogs, birds and amphibians can walk in and out. Steep sides are the classic reason hedgehogs drown.

Line with a butyl or EPDM liner over a generous layer of soft sand and a geotextile fleece — sharp flints will puncture a liner given half a chance. Allow plenty of overlap and tuck the edges under turf or flat stones so the liner disappears.

Fill with rainwater from a butt if you can, which is soft and free of the chlorine and nutrients in tap water. If you must use mains water, let it stand for a few days before adding plants, and accept that it may trigger a flush of algae in the first weeks. Then be patient: a new pond looks raw, then goes green, then — usually by the second summer — settles into clarity as plants and invertebrates find their balance.

Plant Native, and Leave the Fish Out

Fish and wildlife ponds do not mix. Goldfish and even modest carp will hoover up frogspawn, tadpoles, dragonfly larvae and almost everything else that moves, and their waste feeds the algae that turns water to pea soup. Leave them out.

Planting should be British natives, ideally grown from local stock. For the margins, consider marsh marigold, water forget-me-not, ragged robin, lesser spearwort, water mint and yellow flag iris, though the iris can be thuggish in a small pond, so keep it in a basket. For the deeper water, hornwort and water starwort are excellent oxygenators, and a water lily will shade the surface and suppress algae once established.

What you must avoid are the invasive non-natives. Floating pennywort, New Zealand pygmyweed, water fern and water hyacinth can smother a pond and are illegal to plant in the wild. Never take plants, spawn or frogspawn from a wild pond or a neighbour's; buy from a reputable nursery, or let the wildlife arrive on its own. It will, and usually faster than you expect — dragonflies are often the first customers, sometimes within days.

Keeping It Healthy Through the Year

A wildlife pond wants minimal intervention, but a little timely housekeeping makes a difference.

• Twice in summer, pull out excess duckweed and blanket weed by hand, leaving it on the edge for a day so anything caught up can crawl back in.
• Net out fallen leaves in autumn. Sinking leaves are the single biggest source of nutrient overload in a small pond.
• Leave the margins and nearby rough grass long over winter. Frogs, newts and hedgehogs all use that tangle as cover and hibernation.
• Top up in dry spells with rainwater, never a hose if you can help it.
• Add a small log pile or a few stones at the edge, and a ramp of rough stones for anything that falls in.

Do not be tempted to "clean it out". A pond that is emptied and scrubbed each spring is a pond with no life in it. Silt, leaf litter and a bit of green are the whole point. If children are about, a simple mesh cover over the deepest section for the first few years is a sensible precaution rather than a surrender of the pond's wildness.

What You Will See

Within a year you can reasonably expect common frogs and smooth newts, pond skaters, water boatmen, damselflies and, if you are fortunate, a broad-bodied chaser patrolling the margins. Toads may arrive to spawn in early spring, and bats will hunt the insects rising off the surface at dusk. Keep a shallow dish of water near the ground for hedgehogs, and you have joined up a small corridor of habitat that reaches well beyond your own boundary hedge. In a country garden, that is heritage of the most practical kind.