Small ponds, big benefits

A garden pond is one of the kindest things you can build for British wildlife. Even a modest one — a sunken half-barrel, an old butler sink, or a lined hollow two metres across — can become a nursery for common frogs and a home for smooth and palmate newts. These animals have had a rough few decades: the loss of field ponds, drainage of wet meadows and tidy, chemical-heavy gardens have all taken their toll. Your patch, however small, genuinely matters.

The key thing to understand is that amphibians lead a double life. They need water to breed, but they spend most of the year on land, hunting slugs and insects in damp, sheltered corners. A pond that works for them is never just a pond — it is the water, the plants, the messy edges and the log pile a few feet away. Get all of those right and you will be rewarded with spawn in February, tadpoles through spring, and newts patrolling the shallows on warm evenings.

Get the edges right

The single most common mistake is a pond with steep, straight sides. Frogs and newts need to be able to walk in and out easily, and so do the young amphibians leaving the water in summer. Somewhere between a third and a half of your pond margin should be shallow.

• Build in a shallow shelf. Aim for a section just 5–10 cm deep, sloping gently down to the deeper water. That warm, sunlit shelf is where frogs tend to lay and where spawn develops fastest.
• Add a planted beach. A wedge of soil or gravel covered with marsh plants creates both cover and a gradual slope.
• Give them a ladder. If your pond already has vertical sides, lay a piece of rough timber or a stack of stones at one corner, angled from the water to the grass. It works for amphibians, and for hedgehogs and beetles too.
• Leave the margin wild. Long grass, moss and low vegetation around the edge give froglets somewhere to hide the moment they leave the water.

Plant with natives, not invaders

Plants do three jobs at once: they shelter wildlife, shade the water to keep algae in check, and oxygenate it. Choose British natives wherever you can, and plant a mixture of submerged, floating and marginal species so there is cover at every depth.

• Underwater oxygenators: hornwort, water starwort and curled pondweed.
• Marginals for the shallows: marsh marigold, water forget-me-not, water mint, lesser spearwort and ragged robin.
• Taller structural plants: purple loosestrife and yellow flag iris, which also give emerging insects something to climb.
• Floating cover: a small amount of broad-leaved pondweed, left to spread naturally rather than covering the whole surface.

Please avoid the invasive non-natives that escape into the wider countryside — floating pennywort, New Zealand pygmyweed, water fern and parrot's feather. They can be illegal to plant or cause to grow in the wild, and they will smother a small pond within a season.

Create hiding places on dry land

Once breeding is over, your amphibians move out into the garden and need somewhere damp and safe to spend the summer and winter. Newts in particular are fussy about humidity and love a good pile of decaying material.

• Stack a log pile in a shaded corner, with the bark left on and some logs resting on soil rather than paving.
• Leave a leaf heap in a quiet bed. Frogs will burrow into it as the weather turns cold.
• Build a stone or rubble pile next to the pond, with gaps small enough to feel secure.
• Keep a patch of long grass near the water and resist strimming right to the edge — amphibians sitting in the margins are easily injured.

Keep the water clean and chemical-free

A wildlife pond needs no filter, no pump and no fish. In fact, fish are the enemy of a frog pond: goldfish and even sticklebacks will eat spawn, tadpoles and newt larvae. If you want both, keep them in separate ponds.

• Never use pesticides, slug pellets or weedkillers anywhere near the pond. Amphian skin is permeable, and run-off from a treated path or lawn can wipe out a whole generation of tadpoles.
• Top up with rainwater from a butt rather than tap water, which carries nutrients and chlorine.
• Skip the autumn tidy-up. Leave fallen leaves in the pond and around the edges — they are food and shelter, not mess.
• Allow a little algae and duckweed. Some is healthy; only remove it by hand if it covers more than about half the surface.

Look after them through winter and spring

Frogs and newts often overwinter in the mud at the bottom of the pond, so leave the silt undisturbed. If the surface freezes, do not smash the ice — the shock waves can injure animals below. Instead, float a pan of hot water on the surface until a hole melts through.

In spring, watch for frog spawn in clumps from February and toad spawn in long strings a little later. Resist the urge to move spawn between ponds, which can spread disease and invasive plants. Instead, keep the garden quiet, keep cats indoors at dawn when frogs are active, and enjoy the spectacle. A pond that is good for amphibians is a pond full of life, and it will repay you every single year.