Water is the single most valuable thing you can add to a small garden. A pond barely a metre across will be found within weeks by frogs, newts and insects, and it brings in birds that ignore the bird bath entirely — blackbirds, dunnocks and the odd sparrowhawk stopping to bathe and drink. Dragonflies and damselflies will hunt over it all summer, and hedgehogs come to the edge on warm evenings. All of that from a patch of ground you would otherwise have mown.
You do not need a big hole, an expensive liner or a pump. You do not need fish, either. What follows is the method I would use for a first pond in a courtyard, a terrace or a corner of the vegetable plot.
A rigid preformed liner is the easiest route for a beginner. It holds its shape, it cannot be punctured by a stray fork, and it comes with built-in ledges for marginal plants. A moulded pond roughly 1.2m by 0.8m, with a deepest section of 45–60cm, is ideal: deep enough for frogs to overwinter in the bottom mud, shallow enough to warm quickly in spring.
Site it where it gets sun for part of the day but is not baked all afternoon. Keep it clear of overhanging trees — leaf fall and roots are both a nuisance — and away from the lowest point of the garden, where runoff will fill it with silt and nutrients. Put it somewhere you can see from a window, because you will watch it far more than you expect.
This is the step people skip, and it decides whether your pond is a habitat or a trap. Anything that gets in must be able to get out.
Build a shallow beach at one end using a mix of stone sizes: a few large flat slabs to sit on, gravel for the shallows, and at least one route stacked like a staircase from the waterline to dry ground. Hedgehogs, frogs and the occasional mouse will all use it. Stones also hide the rim of the liner and soften the edge, which makes the whole thing look as though it belongs there.
Submerge a couple of rocks partly below the surface. Dragonfly nymphs climb them when they are ready to emerge, and they give insects somewhere to haul themselves clear of the water.
Native plants feed native insects, and that is the whole point. Aim for two or three marginal species and one oxygenator — more than that and a small pond quickly disappears under greenery. Plant in aquatic baskets of two or three litres, using loam-based compost topped with gravel to stop it washing out. Set marginals on the ledge so the crown sits no more than 5–10cm below the surface; oxygenators can go deeper.
Avoid floating pennywort, parrot's feather, water fern and Canadian pondweed. All are invasive, some are banned from sale here, and they will swamp a small pond within a season. Mixed "pond collections" from garden centres often contain exactly these, so buy named natives instead.
Stocking a wildlife pond with goldfish is the most common mistake. Fish eat tadpoles, newt larvae and dragonfly nymphs — in other words, everything you built the pond for. Their waste feeds algae, the water turns green, and you end up buying a filter and a pump to solve a problem you created. A pond without fish settles into its own balance: plants take up the nutrients, water fleas graze the algae, and the water clears by itself after the first spring.
If you want fish, keep them in a separate ornamental pool with proper filtration, and leave this one wild.
Top up in dry spells with rainwater from a butt rather than tap water, which brings in nutrients and chlorine. In autumn, net out some leaves but leave a few — the rotting litter feeds the larval stage of all sorts of creatures. Leave the margins uncut over winter, resist the urge to tidy, and do not be tempted to add fish "just for colour".
By the following February you should have frogspawn, by May the first damselflies, and a pond that asks almost nothing of you beyond a glance over the edge.
The Seasonal Plot shares practical, down-to-earth guidance on british seasonal gardening and outdoor living for readers across the UK.
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