The Leaves Are Already Down: Here's What to Actually Do About Them

Rake a thick, mat-like layer of leaves off the lawn, because it blocks light and moisture and leaves bare or diseased patches by spring. Leave a thin scatter where you can still see grass through it, and leave leaves under hedges, in borders and in quiet corners, where they shelter hedgehogs, ground beetles and lacewings over winter. Clear leaves off paths, where they get slippery. If you do rake, pile them in a corner rather than bagging them, and check any pile for a sleeping hedgehog before you disturb or burn it.

What lives in a leaf layer over winter

Fallen leaves aren't inert once they hit the ground. Leaf litter, or a loosely piled heap of raked leaves, is winter housing for several groups of garden animals.

Hedgehogs build their nests largely out of leaves, moving them into the nest and layeringPropagating a new plant by pinning a low, flexible stem into the soil while still attached to the parent, so it roots before being cut free. Full definition → them into a weatherproof shelter. A messy leaf pile that looks like nothing to a gardener is a ready-made nest site to a hedgehog. Hibernation usually runs from October or November through to March or April, though in mild weather some hedgehogs stay active into December. They aren't fixed in one nest all winter either. They move nest site at least once during hibernation and sometimes use nests other hedgehogs built.

Lacewings, useful predators of aphids in the growing season, hibernate through winter in crevices, leaf litter and evergreen shrubs.

Ground beetles, including the violet ground beetle, shelter in log piles, leaf litter and compost heaps, alongside rove beetles such as the devil's coach horse, often found under logs or pots. These beetles are all predators. The violet ground beetle feeds on slugs, leatherjackets, cutworms and other caterpillars, so a garden that houses them over winter has predators on hand in spring. The same damp leaf litter also gives slugs somewhere to sit out the cold, which is part of why keeping the beetles around matters.

Butterflies and caterpillars also overwinterKeeping a plant alive and intact through the cold months, whether left outdoors, moved under cover, or stored dormant. Full definition →, so shelter such as thick growths of ivy matters, as does cover left standing rather than cleared. Tidying every leaf out from under a hedge or a border removes the kind of ground cover small creatures depend on.

None of this needs a formal habitat structure. A pile in a corner, or leaves left where they fall under a hedge or in a border, does the job.

Do you need to rake?

Not always, and not everywhere. A thin scatter on a lawn, where you can still see grass blades through it, can stay. It breaks down, feeds the soil and does no harm to the turf. A thick layer is different: it smothers the grass, blocking light and moisture, so it needs raking or blowing off. Under hedges, in borders and around shrubs, leave the litter deliberately. The main exceptions are paths, where wet leaves are slippery underfoot, and beds of small or newly planted plants, which a heavy leaf covering can smother in the same way. Away from the lawn and paths, leaving leaves is better for wildlife, not just less work.

Where cleared leaves should go

If the lawn is disappearing under a mat of leaves, or a path has turned slippery, don't bag the leaves for council collection. Push them to the back of a bed or border, where they rot down and enrich the soil while still giving shelter, or gather them into a loose pile in a quiet corner. Either way they keep the shelter value they had on the lawn, just somewhere it isn't a problem. On an allotment or vegetable bed the same thin-and-thick rule applies: a light scatter between rows can break down in place, but a thick layer over young brassicasThe cabbage family: cabbage, kale, broccoli, cauliflower, Brussels sprouts, kohlrabi, swede, turnip and more, sharing the same pests, diseases and rotation rules. Full definition → or overwintering crops should be cleared.

A full autumn's worth of leaves can become leaf mould, a soil conditioner made by composting them in their own space over the following year (making leaf mould has the method). A wildlife pile and a leaf mould cage aren't mutually exclusive. Most leaves take about two years to break down. Oak, beech and hornbeam leaves rot fastest, while thick leaves such as sycamore and walnut are slow and are better shredded first. Shredded leaves can also go into the compost heap, and shredded evergreen leaves break down faster there than in a leaf mould pile.

For a more structured shelter that also suits frogs, toads and other cold-blooded visitors, see building a hibernaculum. A loose leaf pile in a corner is the low-effort version, and it still works.

Check before you disturb a pile

Leaf and log piles are prime hedgehog nesting spots, and because hedgehogs move nests in winter and use nests other hedgehogs built, a pile that looked empty in October may not be empty in January. Before moving a leaf pile, forking over a compost heap or lighting a bonfire built from garden debris, check it thoroughly for a sleeping hedgehog. Check on the day itself rather than relying on an earlier look, and move material gently by hand rather than with a fork. Better still, build a bonfire pile just before lighting, or move and rebuild it first, and check the whole area before strimming. A hedgehog disturbed out of deep winter torpor in cold weather can struggle to recover, so this is the difference between a pile doing its job as shelter and becoming a hazard. If you find an injured hedgehog in Scotland, the SSPCA animal helpline is 03000 999 999.

If you plan to burn garden waste, bonfires and allotment rules covers the rules for burning leaves and prunings.

Common questions

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