Winter Care for Garden Ponds and Wildlife

Why Winter Care Matters for Your Garden Pond

As the days shorten and the first frosts creep in, your garden pond settles into a slower rhythm. But it is far from lifeless. Beneath the surface, fish, frogs, newts and a host of insects are preparing to ride out the cold. A little thoughtful care now can mean the difference between a healthy pond in spring and one that struggles. The good news is that winter pond care is mostly about doing less – but doing the right things at the right time.

Stop Feeding Your Fish

This is the single most important rule for cold weather. As water temperatures drop below 10°C, your fish’s metabolism slows dramatically. They cannot digest food properly, and any pellets or flakes they don’t eat will sink and rot. That rotting food produces ammonia and other toxins, which can poison your fish and turn the water foul. So stop feeding completely once the water is consistently cold – usually from late autumn until early spring.

Don’t worry: your fish won’t starve. They will graze on algae, tiny insects and other natural food found in the pond. If we get a mild, sunny spell and you see fish actively swimming near the surface, you could offer a tiny amount of wheatgerm-based food, but only if they are clearly interested. Otherwise, leave them be. A quiet pond is a healthy winter pond.

Keep a Hole in the Ice

When the pond freezes over, harmful gases like methane and carbon dioxide can build up under the ice, whilst oxygen levels drop. Fish, frogs and newts can suffocate. Keeping a hole open allows these gases to escape and lets oxygen in. It also gives birds and other wildlife a place to drink.

Here are safe ways to maintain an ice-free patch:

• Float a pond heater or an air stone connected to a pump.
• Place a tennis ball or a piece of polystyrene on the surface to prevent a solid freeze.
• If already frozen, rest a pan of hot water on the ice to melt a hole – never pour boiling water directly.
• Never smash the ice with a hammer or stick; the shock waves can injure fish and amphibians.

Aim for a hole roughly the size of a dinner plate, and check it daily during cold snaps.

Leave Decaying Plant Matter for Insects and Amphibians

It is tempting to tidy every dead stem and fallen leaf, but resist the urge. Decaying plant matter is a winter lifeline for wildlife. Hollow stems of reeds, irises and other marginal plants provide shelter for overwintering insects, spiders and even small amphibians. Seed heads feed birds. Fallen leaves at the bottom of the pond create a cosy refuge for dragonfly larvae, water beetles and frogs.

So leave a good portion of standing dead stems – cut them back to about 20–30 cm above the water rather than right down to the base. Let some leaves remain in the pond, but if they form a thick blanket, scoop a few out to prevent oxygen depletion. The aim is balance: enough decaying matter for habitat, but not so much that it decomposes and starves the water of oxygen. This untidy approach is one of the best things you can do for biodiversity.

Extra Care for Frogs, Newts and Other Wildlife

Frogs and newts often overwinter at the bottom of the pond, buried in mud or leaf litter. They need oxygen, which is another reason to keep a hole in the ice. If you have a pond with steep sides, provide a gentle ramp – a piece of wood or a rope – so that any animal that falls in can climb out. Hedgehogs and other small mammals may also visit for a drink, so keep that ice hole accessible.

Birds rely on open water for drinking and bathing in winter. A hole in the ice is a simple gift. Avoid using salt or de-icing chemicals near the pond, as these can run in and harm wildlife. And if you spot a frog or newt moving slowly in cold weather, leave it alone – it is likely fine and just conserving energy.

Simple Checks to Keep Your Pond Healthy

Winter pond care is largely hands-off, but a few quick checks go a long way. Top up the water level with rainwater if it drops, as lower levels can leave fish and plants exposed to freezing. Avoid tap water if you can – it contains chemicals that can upset the pond’s balance. If you have a pump or filter, keep it running to help aeration, but make sure it is not drawing from the bottom where amphibians may be resting.

Check on your pond every few days, especially during prolonged cold spells. Look for fish gasping at the surface, which signals low oxygen – if you see this, increase aeration or make a larger hole in the ice. Remove any excess fallen leaves, but leave some for habitat. And remember: a little decay and a bit of ice are natural. Your calm, thoughtful approach will pay off when spring arrives and the pond bursts back into life.