Making a Home Compost System in a Small Garden

Why a sealed bin suits a small garden

If your garden is more courtyard than country estate, composting can feel like one of those jobs that only works when you have a meadow and a wheelbarrow. It isn't. A sealed bin — the sort with a clip-down lid and a small hatch at the base — is the quiet hero of a tight outdoor space. Because everything stays contained, you don't get fly clouds, a lingering pong or local wildlife rummaging through your leftovers. It also looks tidy: a neat dark cylinder tucked beside a shed, or screened by a couple of pots of lavender, sits happily in even the smallest plot.

The aim is simple: turn kitchen and garden waste into dark, crumbly compost that feeds your pots, beds and window boxes. Get the mix and the routine right, and a well-run bin produces no unpleasant smells and stays pest-free, even in a space the size of a small patio.

Choosing and siting your bin

For most small UK gardens, a 200–330 litre sealed bin is the sweet spot. Look for a clip-down or lockable lid, a hatch at the base for harvesting, and a base plate if you're standing it on paving. A tumbler is a good alternative when space is tight and you'd rather not bend to turn the contents, though it holds less and dries out faster.

Site it somewhere with a bit of warmth but not full sun all day. Partial shade suits composting well and stops the contents drying to a crisp. Bare soil is ideal, so worms and soil microbes can move in through the open base. If paving is your only option, stand the bin on a base plate or a shallow bed of soil, and add a few handfuls of garden soil when you first fill it to get things ticking over.

Above all, keep it within easy reach of the kitchen door. The bin you can get to in slippers on a wet February morning is the bin that actually gets used.

The golden ratio: greens and browns

Composting is a balancing act between two kinds of material. Greens are wet, nitrogen-rich and rot down quickly. Browns are dry, carbon-rich and give the mix structure and air pockets. Roughly two parts browns to one part greens, by volume, is the ratio to aim for.

• Greens: vegetable peelings, fruit scraps, coffee grounds, loose tea leaves, grass clippings in thin layers, spent cut flowers, annual weeds before they set seed.
• Browns: shredded cardboard and plain paper, egg boxes, loo roll tubes, brown envelopes with the windows torn out, straw, chopped twigs, dead leaves, shavings from untreated timber.

Keep a small caddy by the sink with a layer of shredded paper in the bottom. Empty it into the bin, then add a couple of handfuls of browns on top and close the lid. Layering like this keeps the surface dry, which is exactly what keeps fruit flies and smells at bay.

If the contents look sloppy and smell sour, you need more browns. If they're bone dry and nothing seems to be happening, add a splash of water and a handful of greens. Squeeze a fistful: it should feel like a wrung-out sponge.

What to leave out

A sealed bin copes with most kitchen waste, but a few things are best kept out entirely.

• Cooked food, meat, fish, dairy and bones, which attract rats, foxes and flies.
• Dog and cat waste, and used cat litter.
• Diseased plants and perennial weed roots such as bindweed, ground elder and dandelion.
• Glossy magazines, receipts and anything plastic-coated.
• Large quantities of citrus peel or onion skins in one go — fine in small amounts, but they slow things down.

If you'd like to compost cooked food, a bokashi bin on the kitchen worktop is the neat solution for a small home. It ferments the waste indoors without smell, and you then bury the contents in your outdoor bin or a trench in a border.

Turning, aerating and keeping it sweet

Turn the contents with a garden fork every week or fortnight. This one habit is the difference between a bin that works and one that sulks. Turning lets in oxygen, which keeps the process aerobic — and aerobic decomposition is what gives you that pleasant earthy smell rather than a sour, cabbagey one.

A full bin will heat up in the middle as the microbes get going, and it will shrink dramatically as it breaks down. In a cool British climate, expect six to twelve months from a full bin to finished compost. If you have room for two slim bins side by side, so much the better: one matures quietly while the other fills.

Harvesting and using your compost

Finished compost is dark, crumbly and smells like a woodland floor. Lift the hatch at the base and scoop out the oldest material; any lumps that aren't ready can go back in the top. Use it as a mulch around shrubs, fork it into borders, blend it with grit and loam for pots, or steep a handful in water for a simple feed for hungry tomatoes and courgettes.

Even a modest bin will give you a couple of trugs a year, which is enough to make a real difference in a small garden. There's a quiet satisfaction in feeding your pots from a bin that lives behind the shed. A sealed bin, a sensible mix and a fortnightly turn: that's all it takes.