How to start composting at home

Composting is one of the most satisfying sustainable habits you can build — the pile that was kitchen peelings and cardboard a few months ago becomes something genuinely useful for your garden or houseplants. And it is simpler than it looks.

Why compost?

Food and garden waste makes up a large share of what most households throw away. When it goes to landfill and is buried without access to oxygen, it breaks down anaerobically and releases methane — a potent greenhouse gas. Composting instead keeps that material in a controlled aerobic environment where it breaks down into something valuable rather than something harmful.

The benefits are straightforward:

• Less household waste going to landfill or collection — fewer bin bags, lighter bins.
• Free compost — a rich soil improver and mulch that you would otherwise buy in bags.
• Better soil — finished compost improves soil structure, feeds earthworms and beneficial microbes, and helps soil hold both water and nutrients.
• Lower emissions — organic matter composted at home avoids the methane that the same material would produce in an airless landfill.

Choose your method

The right composting method depends on your space, your lifestyle and what you want to compost. There is a workable option for almost every situation.

Outdoor bin or open heap

The classic approach. A simple plastic bin with a lid or an open timber-framed heap in a corner of the garden. Place it directly on soil so worms can get in from below. Add kitchen and garden waste, keep it moist, turn it occasionally and wait. This is the most hands-off method and handles the largest volumes.

Compost tumbler

A sealed drum mounted on a frame that you rotate to turn the contents. Because it is enclosed and you turn it regularly, it heats up faster and can produce finished compost more quickly than a static bin. A good option if you want results faster, if pests are a concern, or if you have a tidy garden where an open pile would look out of place.

Worm bin (vermicomposting)

A layered box system that uses composting worms (not ordinary garden earthworms) to break down kitchen scraps. The worms produce "castings" — one of the richest soil improvers you can get — and a liquid feed you can dilute and use on plants. A worm bin is compact, virtually odourless when maintained correctly, and works perfectly indoors: under the kitchen counter, on a balcony, or in a shaded corner of a flat. This is the best small-space option for people without gardens.

Bokashi

A fermentation system rather than true composting. Kitchen waste — including cooked food, meat and dairy that a standard bin cannot take — is layered in a sealed bucket with bokashi bran (which contains beneficial microbes). The bucket sits on your counter or under the sink. After about two weeks, the fermented material is buried in the garden or added to a traditional compost bin to finish breaking down. Good for flats and for anyone who generates cooked food waste.

Council food-waste collection or community composting

If none of the above suits your situation — no outdoor space, no wish to manage a system — many local councils offer kerbside food-scrap collection. Alternatively, community gardens, allotments, and some farmers' markets run communal compost points where you can drop off scraps.

Greens vs browns — the key balance

Healthy compost needs two types of material in rough balance. Too much of either causes problems.

Greens (nitrogen-rich)

These are the moist, fresh, recently-alive materials. They break down quickly and provide the nitrogen that microbes need to work.

• Fruit and vegetable peelings and scraps
• Coffee grounds and paper coffee filters
• Tea leaves (loose or in paper bags)
• Fresh grass clippings
• Fresh plant and flower trimmings
• Eggshells (add calcium, break down slowly but worthwhile)

Browns (carbon-rich)

Dry, woody, papery materials. They break down more slowly, add structure and prevent the pile from becoming a slimy, airless mass.

• Corrugated cardboard, torn into pieces (remove any tape)
• Newspaper and plain office paper, scrunched up
• Dry autumn leaves
• Straw and hay
• Woody prunings and twigs (chipped or broken small)
• Paper egg cartons and paper bags
• Sawdust or wood shavings from untreated timber

What to avoid

In a standard outdoor bin or heap, leave these out:

• Meat, fish and bones — they attract rats and other pests in an open bin and create foul odours.
• Dairy products — same reasons as meat; can go putrid rather than composting cleanly.
• Oily or heavily cooked foods — including sauces, leftover meals and fried foods.
• Diseased plant material — diseases can survive composting and spread when you use the finished compost.
• Pet waste from cats or dogs — can contain pathogens harmful to humans.
• Treated or painted wood, glossy paper, or anything with lots of synthetic coatings.

The exception: a bokashi system can handle meat, dairy and cooked food because it is a sealed, anaerobic fermentation process. If you want to compost everything from your kitchen, consider pairing a bokashi bucket with a traditional outdoor bin.

The method, step by step

1. Set up your bin or heap

   Position an outdoor bin in a partly shaded spot directly on bare soil — this lets worms migrate in and helps drainage. For a worm bin or bokashi bucket, find a cool, dark spot indoors or in a shaded shed. You do not need to add worms to an outdoor heap; they will find it.

2. Start with a base of coarse browns

   Add a layer of twigs, torn cardboard or dry leaves to the bottom. This keeps the base airy and well-drained from the start, which helps the whole pile stay aerobic.

3. Layer greens and browns as you add material

   Each time you add a portion of fresh kitchen scraps or grass clippings, add a similar volume of browns on top — torn cardboard works perfectly. This layering keeps the pile balanced, reduces smells and speeds decomposition.

4. Keep it as moist as a wrung-out sponge

   Squeeze a handful: it should feel damp but not drip. In dry weather, water it lightly with a can. In very wet conditions or if the pile smells, add more browns to absorb the excess moisture and cover the bin.

5. Turn or aerate every week or two

   Use a garden fork or a compost aerator tool to turn the pile, moving material from the outside to the centre. This introduces oxygen, which the decomposing microbes need. Turning regularly can dramatically speed up the process. Even one turn a month makes a difference over doing nothing.

6. Wait for it to finish

   Stop adding material to a batch and let it cure. Finished compost looks dark brown and crumbly, has no recognisable food scraps remaining, and smells pleasantly earthy — like forest soil. If bits of cardboard or tough stems are still visible, give it more time or screen it.

7. Harvest and use

   Scoop finished compost from the hatch at the base of a traditional bin, empty a tumbler when the batch is done, or collect castings from the lower tray of a worm bin. Use it in the garden or pass it on to neighbours who garden.

Troubleshooting common problems

• Bad smell (sour or rotten): The pile is too wet or has too many greens. Add a generous layer of torn cardboard or dry leaves and turn it to introduce air.
• Bad smell (sulphurous, like bad eggs): The pile is waterlogged and has gone anaerobic. Dig it over thoroughly to aerate it, add lots of browns, and consider covering the top to stop more rain getting in.
• Not breaking down: The pile is probably too dry or has too many browns. Add kitchen scraps and a little water, then turn it.
• Fruit flies: Bury fresh kitchen scraps under a layer of browns each time you add them, and keep the lid on. Fruit flies cannot access material that is covered.
• Rodents or pests: Avoid adding meat, dairy or cooked food. Switch to an enclosed bin with a solid base rather than an open heap. A tumbler is particularly good at keeping pests out.
• Pile not warming up: A pile that is too small, too dry or lacking nitrogen-rich greens will stay cold. Make the pile bigger, add greens, and water if dry. Cold composting still works — it just takes longer.

Using finished compost

Home compost is a versatile soil improver rather than a fertiliser — it feeds the soil biology and improves structure rather than delivering concentrated nutrients. Here are the most useful ways to apply it:

• Dig it into beds and borders before planting. A few centimetres mixed into the top layer of soil improves moisture retention and feeds soil life.
• Use it as a surface mulch. Spread a layer over the soil around plants to suppress weeds, retain moisture and gradually feed the soil as it breaks down further.
• Mix it into potting compost for containers and raised beds — typically up to a third compost to two thirds potting mix.
• Top-dress a lawn by brushing a thin layer of sieved compost into the grass in autumn to improve thin or worn patches.
• Give it away. If you have more than you can use, neighbours, community gardens and local growing groups are usually very happy to take finished compost off your hands.

Quick-start checklist

• Choose a method that suits your space (bin, tumbler, worm bin or bokashi).
• Set up your bin or worm bin this week.
• Put a small container with a lid on the worktop to collect scraps before each trip to the bin.
• Stock up on browns — start a bag of torn cardboard near the bin.
• Add a layer of browns every time you add greens.
• Turn or aerate the pile at least once a fortnight.
• Check moisture: damp like a wrung sponge, not wet or bone dry.
• Wait — and use the finished compost on your beds, pots or lawn.