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

If you want to bring wildlife into your garden quickly, nothing beats water. A pond the size of a dining table will draw in more species than a hedge, a meadow and a bug hotel put together. Within days of filling it, insects arrive as if from nowhere: pond skaters skating on the surface film, diving beetles, water boatmen and the first egg-laying dragonflies. Within a season, amphibians find it. Common frogs can travel a kilometre or more across fields and gardens, and they are remarkably good at sniffing out new water.

That matters, because amphibians have had a hard time of it. Thousands of small farm ponds were lost in the twentieth century, and the survivors are often isolated, fish-stocked or shaded to death. A well-made garden pond is not a decorative extra; for a frog, a toad or a smooth newt, it can be a lifeline.

Siting and Shaping Your Pond

Choose a spot that gets sun for at least half the day, especially in the morning, so the water warms up and spawn develops. Some afternoon shade is welcome in a hot summer, but avoid sitting the pond directly under a big tree — you will spend your life scooping out leaves, and the roots will fight your liner.

Size matters less than shape. Even a metre by a metre and a half works. What amphibians need is:

• A deep point of around 60–75cm so the pond does not dry out in summer and frogs have somewhere to overwinter in the mud.
• Gently sloping sides and a shallow shelf at 20–30cm where spawn and marginal plants can sit.
• At least one soft, shelving edge — not a vertical wall of stone or steep preformed plastic.

Fill it with rainwater from a butt if you can; it is softer and free of the chlorine and nutrients in tap water. Have a plan for where the water goes in a downpour, so you are not flooding your neighbour's patio.

Planting for Amphibians

Plant natives, and plant in layers. Below the surface, oxygenators such as hornwort and water starwort give tadpoles cover and frogs a place to anchor their spawn. Their leaves also host the algae and tiny invertebrates that tadpoles graze on.

Around the margins, aim for a tangle rather than a tidy border. Good, reliable choices include marsh marigold, water forget-me-not, brooklime, water mint, lesser spearwort and ragged robin. Yellow flag iris is beautiful but vigorous, so give it room or keep it in a sunken pot.

What you plant outside the water matters just as much. Leave a patch of long grass, a log pile, a heap of stones and some leaf litter nearby. Frogs and newts spend most of the year on land, and they need damp, cool cover in summer and a frost-free refuge in winter. A compost heap is a five-star amphibian hotel.

Do not plant floating pennywort, parrot's feather, water hyacinth or New Zealand pigmyweed. They are invasive, they spread fast, and allowing them to escape into the wild is an offence in England and Wales.

Leave the Fish Out

This is the single most important rule. Goldfish, sticklebacks and even the humble minnow will strip a pond of tadpoles and newt larvae within weeks. A pond with fish is, almost without exception, a pond without amphibians. A small barrel of goldfish in a courtyard is fine — just keep it well away from your wildlife pond.

The same caution applies to other introductions:

• Do not move spawn, tadpoles or pond plants from another pond. You risk carrying ranavirus, chytrid fungus and invasive species.
• Do not add ducks or ornamental wildfowl. They eat spawn, trample plants and foul the water badly.
• Be careful with pumps and fountains. Unprotected intakes trap tadpoles and newt larvae. If you want moving water, choose a pump with a fine guard and keep the surface calm.
• Keep pesticides, slug pellets and fertiliser well away. Run-off from a treated lawn can wipe out a pond's invertebrates in a single season.

Safety for Wildlife and People

Every pond needs somewhere for a creature to climb out. A half-submerged log, a sloping stone beach or a piece of rough timber wedged at the edge gives hedgehogs, frogs and fledglings a route to dry land. Hedgehogs drown surprisingly often in steep-sided garden ponds, and it is a sad and entirely avoidable death.

Resist the urge to net the whole surface. Frogs, newts and birds get tangled in fine netting, and it makes the pond ugly to boot. If leaves are a real problem, use a rigid mesh held well above the water on a frame. If small children use the garden, a sturdy fence with a self-closing gate is the sensible answer.

A Year of Gentle Care

Spring is for watching, not tidying. Frogspawn appears from late February, toad spawn in long strings a little later, and newts lay eggs folded into plant leaves. Leave it all alone and keep the water level steady.

In summer, top up with rainwater during dry spells and let the grass grow long at the edges. In autumn, skim some leaves but not all — a little leaf litter is food and cover, while a thick, rotting blanket will starve the water of oxygen.

Never smash ice in winter. The shock waves can kill amphibians resting in the mud below. Instead, float a ball in the pond or stand a pan of hot water on the surface to melt a hole. If the pond needs clearing, do it in late September or October, and leave the sludge on the side for a day so that every creature can crawl back home.