Why a Pond Is the Best Thing You Can Add to a Wildlife Garden

Of all the features you can add to a garden, a pond delivers the biggest return for the least effort. Within days of filling it, you will see insects skating across the surface. Within weeks, dragonflies will be patrolling above it. By the following spring, frogs will have found it, and if you are lucky, they will breed in it. A pond also gives garden birds somewhere to drink and bathe, which is especially valuable in dry spells when other water sources disappear.

The good news is that you do not need a large pond, a pump, or any filtration at all. A wildlife pond is deliberately simple: no fish, no fountain, no chemicals. What it does need is the right shape, the right plants, and a little patience.

Choosing the Spot and the Size

Aim for at least one square metre of surface area, though two or three is better. Depth matters more than width: somewhere between 45cm and 60cm at the deepest point gives amphibians a safe place to overwinter and stops the pond drying out in summer. Shallower than that and frogspawn may be caught by a late frost.

Position the pond where it gets sun for at least half the day. Dragonflies and damselflies need warmth to hunt and display, and most aquatic plants flower poorly in shade. Avoid sitting it directly beneath a large deciduous tree, as falling leaves will rot down and turn the water stagnant. A spot that is partly sheltered from the wind will also keep the surface calmer, which suits emerging insects.

• Keep one edge in light shade so wildlife has a refuge on hot days.
• Leave a gap in nearby planting so birds have a clear flight path in and out.
• Check for buried cables and drains before you dig.

Getting the Shape Right: Shallow Edges Matter

The single most important design feature is a gentle, shallow shelf around at least part of the perimeter. Frogs, toads and newts enter and leave the water by walking, not leaping, and they need a gradual slope. A beach of pebbles or a shelf just a few centimetres deep lets them climb out easily and gives dragonfly larvae a place to haul themselves up before their final moult.

Build in a range of depths if you can: a shallow marginal zone for plants, a mid-depth shelf, and one deeper basin. This variety creates different micro-habitats and supports far more species than a uniform tub of water.

If you use a flexible liner, line the top of it with turf or flat stones so it disappears. Wildlife will find the pond faster if it looks natural rather than bright blue.

Planting for Wildlife, Not Just Looks

Native plants are the backbone of a good wildlife pond. They oxygenate the water, shelter larvae, and provide the stems that dragonflies and damselflies use to climb out when they emerge. Aim for a mix of submerged, floating and marginal species.

• Submerged oxygenators: hornwort and water starwort keep the water clear without needing any machinery.
• Floating plants: frogbit and water lilies provide shade and resting places for insects and emerging frogs.
• Marginals: marsh marigold, water forget-me-not, ragged robin and flowering rush soften the edges and give cover.
• Emergent stems: rushes, sedges and iris are ideal for climbing out of the water.

Plant in baskets of ordinary garden soil topped with gravel, or straight into the marginal shelf. Avoid fertiliser, and never introduce invasive species such as parrot's feather or New Zealand pygmyweed.

Making It Safe for Frogs and Birds

Frogs will arrive on their own. You do not need to move spawn or adults in from elsewhere, and doing so can spread disease. What you can do is make the surrounding garden welcoming. Leave a patch of long grass, a log pile or a stone heap nearby so amphibians have somewhere damp to hide between visits.

Birds drink and bathe at the shallow edge, so keep at least one section free of dense planting. If your pond has steep sides, add a gently sloping ramp of stones or a piece of untreated timber so anything that falls in can climb out. Hedgehogs and other small mammals drown in steep-sided ponds surprisingly often.

Never use pesticides, slug pellets or weedkillers anywhere near the pond. Amphibians absorb water through their skin, and runoff is quickly lethal.

A Little Maintenance, and a Lot of Reward

Wildlife ponds need far less work than ornamental ones. In autumn, scoop out fallen leaves before they sink and rot. In late summer, thin out any oxygenators that have covered more than about half the surface, leaving the cuttings on the edge for a day so any trapped creatures can crawl back.

Do not clean the pond out or change the water. A slightly murky, green-tinted pond is a healthy one, full of the microscopic life that feeds everything above it. Resist the urge to tidy too much.

Then simply wait and watch. The first damselflies usually appear the same summer. Frogs often take a year to find you, sometimes two. When the first clump of spawn appears in spring, followed by a chorus of croaking on warm evenings, you will know the pond has become exactly what you hoped for: a small, busy, self-supporting patch of British wildlife.