Emily Hartley
Why hedgehogs need a helping hand
Hedgehogs are one of Britain's most beloved mammals, but their numbers have fallen dramatically in recent decades. A single garden, however wildlife-friendly, is rarely enough to support them. Hedgehogs are nocturnal wanderers, travelling up to two kilometres in a single night in search of beetles, caterpillars, earthworms and slugs. They also need to find mates and, in autumn, a safe place to hibernate. Solid fences and walls fragment the landscape into tiny islands, leaving hedgehogs trapped, hungry and vulnerable. The good news? A simple gap — just 13 centimetres square — can reconnect your garden to the wider neighbourhood and make a real difference.
What is a hedgehog highway?
A hedgehog highway is simply a series of small gaps in fences, walls and other boundaries that allow hedgehogs to move freely between gardens. Think of it as a network of tiny doorways. Each gap needs to be at least 13 centimetres (about 5 inches) wide and high — roughly the size of a CD case. Any smaller and a hedgehog may get stuck; any larger and you risk letting in unwanted visitors like rats, though a 13cm gap is generally too small for most adult rats. The gaps should be at ground level, with no lip or step, so hedgehogs can walk straight through. A well-placed highway can connect dozens of gardens, giving hedgehogs access to a much larger territory.
How to create a gap in a fence
Most garden fences are made of timber panels or gravel boards. Creating a hedgehog hole is straightforward, but always check with the fence owner first — if it is not your fence, you will need permission. For a wooden panel, use a jigsaw or a hand saw to cut a square or arch-shaped hole at the bottom edge. A 13cm by 13cm square is ideal. If you are cutting into a gravel board (the horizontal board at the base of the fence), make sure the gap goes right down to the soil. Smooth any rough edges with sandpaper, and remove splinters. If you prefer not to cut, you can simply lift a panel slightly and prop it up with a brick or two, creating a tunnel underneath. However, this can be less stable, so cutting a proper hole is usually better. Always make sure the gap is clear of obstructions — no stones, roots or thick grass blocking the entrance.
Dealing with walls and other barriers
Brick walls and stone boundaries need a different approach. You can remove one or two bricks at ground level to create a gap, but check that the wall is not load-bearing and that you are not weakening it. If in doubt, consult a builder. A neat solution is to insert a small length of plastic pipe or a purpose-made hedgehog tunnel through the wall, but a simple gap is often enough. For concrete or metal fences, you may need to dig a small channel underneath or create a gap at the base. Remember that hedgehogs are strong diggers, but they cannot tunnel through solid concrete. Never use chemicals or sharp edges near the gap — hedgehogs have delicate noses and feet.
Making your garden hedgehog-friendly
A highway is only useful if the gardens at each end are safe and welcoming. Once you have created your gap, take a few extra steps to make your garden a hedgehog haven. Provide a shallow dish of fresh water — hedgehogs get very thirsty, especially in summer. Avoid slug pellets and other pesticides, which are lethal to hedgehogs. Check before strimming or mowing long grass, and always look inside bonfires before lighting them. Leave a wild corner with log piles, leaf litter or a purpose-built hedgehog house for nesting and hibernation. If you have a pond, ensure there is a gentle ramp or sloping edge so hedgehogs can climb out. Feed hedgehogs with meat-based cat or dog food, not bread or milk, which can cause digestive problems.
Getting neighbours involved
A single gap is a start, but a true highway needs a chain of connected gardens. Talk to your neighbours — most people are happy to help once they understand the problem. You could suggest a shared map of gaps on your street, or simply ask each household to create one hole in their boundary. Even a few connected gardens can make a huge difference. If you live in a rented property, ask your landlord for permission. For those with large boundaries, consider leaving a wild strip along the fence line. Every gap counts. By working together, you can turn a fragmented neighbourhood into a safe, continuous route for hedgehogs, helping them find food, mates and shelter for years to come.
