Making Your Own Compost in a Small Space

Why a small garden can still make good compost

There is a persistent myth that composting belongs to sprawling gardens with three-bay wooden systems and a wheelbarrow parked in the corner. In practice, a modest courtyard, a balcony or even a two-metre patch beside the back door can host a perfectly productive bin. What matters is not how much space you have, but how well you look after the contents.

Small-space composting also gives you something back week by week. Every teabag, banana skin and courgette end you keep out of the wheelie bin is weight your council does not have to collect, and every bucketful of finished compost is money you do not have to spend on soil improver. For anyone gardening on a tight patch, that is a quiet sort of luxury.

Choosing a bin that suits your space

Before you buy anything, measure the spot. You need room to lift a lid or turn a drum, and you need somewhere you will actually walk to in the rain. A level, well-drained corner in part shade is ideal; full sun will dry a small bin out quickly, while deep shade can leave it cold and sluggish.

• Dalek-style bin: the familiar plastic cone, usually 220 to 330 litres. Cheap, neat and fine for a small garden, though you have to fork the contents out through the hatch at the bottom.
• Tumbler: a rotating drum, typically 100 to 200 litres. Excellent where you have no room to wield a fork, and turning is a ten-second job.
• Wormery: a stack of trays roughly the size of a recycling box, ideal for a balcony or a paved yard. It takes kitchen scraps only and produces both worm compost and a liquid feed.
• Bokashi bucket: a sealed indoor bin that ferments cooked food, meat and dairy. Useful if you want to keep everything under the sink, though the resulting mush still needs burying or adding to a bin to finish.

Whichever you choose, stand it on bare soil or paving rather than a wooden deck, and consider a sheet of fine mesh beneath it if rats or mice are known in the area.

Getting the greens and browns right

Everything comes down to balance. Greens are the soft, wet, nitrogen-rich materials: grass clippings, vegetable peelings, spent flowers, coffee grounds, annual weeds before they set seed, and comfrey leaves. Browns are dry, carbon-rich and structural: scrunched cardboard, egg boxes, toilet roll tubes, shredded paper, straw, autumn leaves and untreated sawdust.

Aim for roughly two to three parts brown to one part green by volume. In a small bin this matters more than in a big heap, because there is less mass to buffer mistakes. The test is simple: squeeze a handful. It should feel like a wrung-out sponge. Slimy and sour means too much green; dusty and bone-dry means too much brown.

Two small-space refinements are worth knowing. First, tear or shred everything before it goes in, since a small bin cannot chew through a whole cabbage stem. Second, snip teabags open or use loose leaves, as many bags contain plastic mesh that will still be there in a year's time.

Wormeries and the kitchen-scrap approach

If your outdoor space is a balcony or a concrete yard, a wormery is often the better answer. It uses brandling worms, sometimes sold as tiger worms, which are not the same as the earthworms in your borders. They live in the top few inches of rotting material and work astonishingly fast.

• Keep the bedding damp but not sodden, using shredded paper or coir.
• Bury scraps rather than tipping them on top, which discourages fruit flies.
• Go easy on onions, citrus peel and anything spicy; the worms will tolerate small amounts but not a glut.
• Site the wormery in shade and insulate it in winter, or move it into a shed or garage during hard frosts.

Draw off the liquid from the tap every week or two and dilute it roughly one part to ten with water before using it on pots and containers.

Turning, moisture and common grumbles

Small bins rarely get hot enough to compost quickly, so a little help goes a long way. Turn the contents every fortnight or so, either with a fork or a purpose-made aerating tool, bringing the outside to the middle. If the bin is a tumbler, give it five or six full rotations twice a week.

Most problems have obvious causes. A sour smell or a slimy texture means too wet and too green, so add cardboard and turn. Fruit flies suggest uncovered scraps, so bury them. A dry, inert bin needs a watering can and a handful of grass clippings. Rats and mice are drawn by cooked food, meat and dairy, so keep those out of an open bin and use a wormery or bokashi instead.

Knowing when it is ready to use

Depending on the season and the size of your bin, expect finished compost in six to twelve months. It is ready when it looks dark, crumbles in your hand and smells of woodland floor rather than rubbish. Any lumps, eggshell or woody stems left behind can be sieved out and returned to the next batch.

Use it as a mulch around shrubs, fork it into vegetable beds, or mix it with leafmould and grit for potting. Even a small bin, tended patiently, will quietly transform your soil and your garden along with it.