Start with a bin that fits your space

You do not need a corner of an orchard to make good compost. A courtyard, a narrow side return or a balcony with a bit of shelter will do, provided you choose a bin that suits your footprint and your patience. For most urban gardens, a 220 to 330 litre upright bin — the tapered "dalek" style many councils supply — is the sensible default. It takes up roughly the space of a wheelie bin, holds a surprising amount, and its shape keeps the contents reasonably insulated. If turning is difficult for you, a 100 to 200 litre tumbler on a stand is a decent compromise, though it dries out faster and holds less.

Siting matters more than people expect. Choose a spot in partial shade, where the bin will not bake in summer or sit in a puddle all winter. Stand it directly on soil or on paving with a few inches of crumbled soil or old compost underneath, so worms and soil microbes can move in. Leave a gap from fences and neighbours' windows — not for any dramatic reason, but because a well-run bin has only a faint earthy smell, and you want to keep it that way rather than testing the relationship. If you have no soil at all, a wormery is the better answer for a balcony: it handles kitchen scraps quietly, produces liquid feed, and takes up less than a square metre.

The greens and browns balance

Everything else in composting is detail. Get the balance roughly right and the bin looks after itself. "Greens" are soft, wet, nitrogen-rich materials. "Browns" are dry, fibrous, carbon-rich ones. Aim for roughly two parts browns to one part greens by volume — or, more simply, a couple of generous handfuls of browns for every handful of kitchen scraps.

• Greens: fruit and vegetable peelings, tea leaves and coffee grounds, grass clippings, spent houseplants, cut flowers, annual weeds without seed heads.
• Browns: torn cardboard and egg boxes, newspaper, toilet roll tubes, kitchen paper, autumn leaves, straw, woodchip, untreated sawdust, shredded confidential post.

The single most common mistake in a small bin is too many greens. A bin of pure kitchen waste goes slimy, anaerobic and sour in days. Cardboard is your best friend here — keep a flattened box beside the bin and tear a couple of pieces in every time you add a caddy of peelings. Chop things up as you go. A banana skin cut into four breaks down in weeks rather than months, and a quick pass with the knife while you are already at the chopping board costs nothing.

What to keep out

A cool, small-scale bin will not reliably kill pathogens or break down fats, and the wrong items attract exactly the visitors you are trying to avoid. Leave out:

• Cooked food, meat, fish, bones, dairy and oils — these are the main draw for rats, foxes and gulls.
• Dog and cat faeces, and used cat litter.
• Diseased plant material, especially anything with blight or clubroot.
• Perennial weed roots such as bindweed, ground elder and couch grass, plus any weed that has already set seed.
• Glossy magazines, receipts and anything plastic-coated — they will still be there in five years.

Eggshells, citrus peel and onion skins are all fine, contrary to folklore. They break down slowly, which is no bad thing.

Keeping pests, smells and neighbours happy

The trick with kitchen scraps is to never leave them on the surface. Keep a lidded caddy on the worktop, empty it every two or three days, and bury the contents in the middle of the bin, pulling browns over the top afterwards. If rats are a genuine local problem, use a bin with a base plate or stand it on a paving slab, and consider a bokashi-style fermented bran system indoors first — the fermented scraps are less appealing to vermin and can then go into the bin or straight into a trench in a flower bed.

Fruit flies mean exposed fruit waste; bury it deeper. A sour, ammonia-ish smell means too many greens and not enough air — add cardboard, give it a turn, and it will settle. A bone-dry bin means too many browns; add a caddy of peelings and a little water. Aim for the consistency of a wrung-out sponge.

Managing it through the year

Turn the contents with a fork every fortnight or so if you can, mixing the outside to the middle. Small bins rarely get hot enough to speed things along dramatically, so expect six to twelve months rather than six weeks, and do not worry about it. Add a handful of garden soil or finished compost now and then as a starter. In winter, everything slows to a crawl — keep adding, keep the lid on against the rain, and it will catch up in April. If the bin fills before it finishes, start a second one or bag the surplus in old compost sacks with holes punched in the sides.

When it's ready, and what to do with it

Finished compost is dark, crumbly and smells of woodland floor. You will still find the odd eggshell and woody stem; that is normal. A well-managed 220 litre bin in a two-person household will give you roughly 50 to 80 litres a year, which is two or three bags' worth — enough to matter in a small garden. Use it as a mulch around shrubs and perennials, fork it into borders, or mix it with grit and old potting compost for containers and top dressing. Sieve the coarser bits and return them to the next bin as a starter. Even in a space the size of a parking bay, that is a decent return on a bag of peelings.