Why Compost Deserves a Place in Every Wildlife Garden

Composting is one of those rare jobs that rewards you twice. You get a free, rich soil improver for your borders and pots, and you get a living, breathing habitat that supports everything from brandling worms to hibernating hedgehogs. In a British garden, where our soils range from heavy clay to thin, sandy loam, good compost is the single most useful thing you can add. It holds moisture in dry spells, improves drainage in wet ones, and feeds the soil life that in turn feeds your plants.

You do not need an expensive bin or a neat three-bay system. A corner behind the shed, a wire ring under a hedge, or even a few stout bin bags will do the job. What matters is getting the mix roughly right and then leaving nature to finish the work.

Leaf Mould: The Easiest Autumn Job There Is

If you only do one thing this autumn, rake up your leaves. Leaf mould is quieter and slower than compost, but it is superb for woodland plants such as ferns, hellebores, wood anemones and bluebells. It is also low in nutrients, which makes it ideal as a seed-sowing mix or a mulch for wildflower areas where you do not want to encourage lush, floppy growth.

Gather leaves when they are damp but not sodden. Oak, beech and hornbeam break down slowly and can take two years. Sycamore, lime, ash and horse chestnut rot much faster, often within a year. If you mix the two, you will get a usable product sooner. There are three simple methods:

• Wire ring: drive four stakes into the ground, wrap chicken wire around them, and tip the leaves in. Keep it damp and turn it once or twice if you remember.
• Bin bags: fill black bags, poke a few drainage holes, tie loosely, and tuck them behind a shed. Check after twelve months.
• Cardboard box or old compost bag: good for small gardens and courtyard plots.

Leave a few leaves in borders and under hedges, though. They shelter overwintering ladybirds, hedgehog fleas and moth pupae, and blackbirds will spend happy hours turning them over looking for food.

Building a Garden Compost Heap

A heap works best at around a cubic metre. Smaller than that and it struggles to heat up; much larger and it can go anaerobic and smelly. Site it on bare soil if you can, so worms and soil microbes can move in from below. Part shade is fine, and a bit of shelter from drying wind helps.

The old rule is to balance greens and browns. Greens are soft, wet and nitrogen-rich. Browns are dry, woody and carbon-rich. Aim for roughly equal volumes, layered like lasagne, and turn the heap every few weeks if you want fast results. A well-made heap will heat to 60–70°C in the middle, which kills many weed seeds and pathogens.

If you would rather not turn it, that is fine too. A cool heap takes longer, but it is far better for wildlife. Frogs, toads, slow worms and grass snakes all use cool heaps, and a slow worm tucked under a piece of old carpet on top of a compost pile is one of the quiet pleasures of a British garden.

What to Add and What to Leave Out

Variety is the secret. The more different materials you add, the more complete the finished compost.

• Add: grass clippings in thin layers, annual weeds before they seed, vegetable peelings, tea leaves and coffee grounds, crushed eggshells, torn cardboard, shredded paper, vacuum dust, pet and human hair, wool offcuts, spent bedding plants, and the contents of your hoover bag.
• Leave out: cooked food, meat, fish and dairy, which attract rats; perennial weeds such as bindweed, ground elder and couch grass; diseased plant material; glossy magazines; cat and dog waste; and anything plastic, including some tea bags, which often contain a hidden plastic mesh.

If the heap gets slimy, add more browns. If it is dry and doing nothing, water it and add more greens. A heap should feel like a wrung-out sponge: damp, not dripping.

Compost as Habitat

Think of your heap as a small, warm, damp nature reserve. Brandling worms do the heavy lifting, but they share the space with centipedes, millipedes, ground beetles, springtails and slugs. These in turn feed robins, wrens, shrews and hedgehogs. A heap left undisturbed over winter may shelter a hibernating hedgehog or a toad, so always check before you fork it over — a gentle prod with a fork handle is kinder than a sharp spade.

If you can, keep two heaps: one you turn and use, and one you leave alone for a year or more. That second, older heap is where the real wildlife value lies. Add a small log pile beside it, and you have instant habitat for stag beetle larvae and solitary bees.

Using Your Compost Through the Seasons

Spread finished compost in spring as a mulch around shrubs and perennials, and again in autumn to protect bare soil over winter. Use leaf mould as a top dressing for woodland planting, or sieve it for seed sowing. Neither needs to be dug in — worms and rain will pull it down for you, which is exactly how a woodland floor works.

Start small, keep it simple, and let the heap do the rest. Within a year you will have darker, crumbly soil, fewer trips to the garden centre, and a garden that hums, rustles and burrows with life.