What can I put in my compost bin? The UK list
"Can this go in the compost?" is one of the first questions anyone asks when they start. It matters too, because research shows that knowing how to compost is one of the things that decides whether people start at all. I wrote about that in why people give up composting.
The good news is that the rules are simple once you know them. This is the list we use for our own bins, based on advice from the RHS and Garden Organic. If you want to check one particular thing, the A to Z list has plain answers for over 200 everyday items.
The one rule that matters. Greens and browns
Almost everything that goes in a compost bin is either a green or a brown.
- Greens are soft, wet, leafy things like fruit and veg peelings, grass cuttings and spent plants. The RHS describes them as "rich in nitrogen".
- Browns are dry, woody or papery things like cardboard, egg boxes, shredded paper, dead stems and twiggy prunings. The RHS describes them as "rich in carbon".
The RHS suggests making 25 to 50 per cent of your bin greens, with the rest browns. Garden Organic suggests roughly equal amounts of each by volume, and calls that a rough guide you'll learn to judge by eye.
In a kitchen bin, most of what you throw in is green. So the habit that makes the biggest difference is adding a handful of torn-up cardboard or egg box with your peelings. That's what stops a bin going wet and slimy.
Yes please. What can go in
From the kitchen
- Raw fruit and veg peelings and scraps, including banana skins, apple cores and onion skins. Cover fresh scraps with a few leaves or torn card to keep fruit flies away.
- Coffee grounds, paper filter and all.
- Eggshells, rinsed and crushed so they break down faster.
- Mouldy fruit and veg. Mould is just composting starting early.
- Kitchen roll and paper towels, as long as they haven't been used with cleaning sprays, bleach or oil.
Paper and card
- Plain cardboard, torn up, with tape, labels and staples removed.
- Egg boxes, toilet roll tubes and cereal boxes. Garden Organic lists all three as browns.
- Shredded paper, mixed in rather than added as one big wad.
From the garden
- Spent veg plants like courgettes, beans, peas and lettuce, with woody stems chopped.
- Annual weeds, as long as they haven't flowered or set seed.
- Grass cuttings, in thin layers mixed with browns. On their own they "can become a slimy, smelly mess", as the RHS puts it.
- Bedding from vegetarian pets like rabbits and guinea pigs.
Check first. Fine in the right form
- Teabags. Many teabags contain plastic to seal them. See the section on teabags below.
- Pizza boxes. Yes, torn up, once the cheese and food are scraped off. Food left on them draws rats.
- Autumn leaves. A few at a time is fine. Big piles are slow and are better made into leaf mould in a separate bag.
- Wood ash. A thin sprinkle of cold ash from untreated wood. Garden Organic says wood ash "in moderation".
- Grass treated with weedkiller. Many lawn weedkillers say not to compost the first few cuts after spraying. Follow the label.
- "Compostable" packaging. Only if it says it's home compostable. See below.
Keep out. What can't go in
- Cooked food and leftovers, meat, fish and dairy. Garden Organic says these "can attract vermin", unless you have a sealed hot composting system.
- Bread, cakes and pastries. A magnet for rats and mice, and they go mouldy and smelly in a small bin.
- Dog poo, cat poo and cat litter. Garden Organic lists cat litter and dog faeces as things not to compost. Pet waste can carry parasites and diseases that a home bin won't kill.
- Disposable nappies. On Garden Organic's not-to-compost list. They contain plastics and gels.
- Coal and coke ash. Also on Garden Organic's list.
- Diseased plants. A home bin doesn't get hot enough to kill many plant diseases, so they could come back when you spread the compost. Use your council's green waste collection instead.
- Weeds with seeds, and perennial weed roots. Seeds survive a home bin, and roots can regrow in it.
- Citrus peel, best left out. It's slow to break down and often waxed, so we leave it out of our small bin. A few bits won't hurt, but if you get through lots, use your council food caddy.
- Glossy paper and shiny or plastic-coated card. The coating won't break down. Recycle it instead.
Most of these are kept out for one of two reasons. Either they attract rats and smell, or a home bin doesn't get hot enough to deal with them safely.
Where the "keep outs" go now
Under the government's Simpler Recycling rules, councils in England must collect household food waste weekly and free of charge from 31 March 2026, although some councils have permission to start later. So cooked food, meat, fish, dairy and bread now have somewhere sensible to go.
The two work well together. Raw peelings, card and garden waste go in your compost bin, and plate scrapings go in the council food caddy.
Teabags and "compostable" packaging
These two catch a lot of people out.
Teabags. Garden Organic says many teabags contain polypropylene to seal them, which "will not break down in the domestic compost heap". Some brands use PLA, a plant-based plastic, instead. A 2024 University of Plymouth study buried teabags in soil for seven months, and the ones made solely from PLA "remained completely intact". Garden Organic's best advice is to use loose leaf tea or plastic-free bags. Failing that, tear the bags open, put the leaves in the compost and the bags in the bin.
Compostable packaging. Look for packaging that says home compostable. Packaging that just says compostable usually needs an industrial site, which runs much hotter than a home bin. Even home compostable plastics can struggle. In the Big Compost Experiment, a UK citizen science study, 60% of plastic certified as home compostable did not fully break down in people's home compost bins.
How we do it with Twin Tip
Our routine is the same every day. Peelings, coffee grounds and torn card go into the small 50 litre bin as we use them. When it's about three-quarters full, we tip it into the big 110 litre bin, which mixes everything without a fork. Cooked food goes in the council food caddy.
Keeping cooked food, meat and bread out matters in any bin, but especially if you're worried about rats. Twin Tip's sealed bins, clip-down lids and 6 mm holes help keep rodents out. What you put in matters just as much.
If you want the list on your fridge, the free compost fridge sheet has the most common items on one page. For anything else, try the quick checker or the full A to Z list.
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Questions people ask
Can I put cooked food in my compost bin?
No. Cooked food, meat, fish, dairy and bread can attract rats and smell. Put them in your council food waste caddy instead. In England, councils must collect food waste weekly from 31 March 2026, although some have permission to start later.
Can teabags go in compost?
Only if the box says the bags are home compostable. Many teabags contain polypropylene or PLA, which don't break down properly in a home bin. Tear the bag open, compost the leaves and put the bag in the bin.
Can I compost cardboard?
Yes, plain cardboard is one of the best things you can add. Tear it up and remove tape, labels and staples. Shiny or plastic-coated card should stay out.
Can I put citrus peel and onions in compost?
Onion skins and raw onion scraps compost fine. Citrus peel is slow to break down and often waxed, so we leave it out of our small bin, though a few bits won't hurt.
What is the right mix of greens and browns?
The RHS suggests 25 to 50 per cent greens, such as peelings and grass, with the rest browns, such as cardboard and woody stems. Garden Organic suggests roughly equal amounts of each by volume as a rough guide.
Can I compost dog poo?
Not in a home compost bin. Dog and cat waste can carry parasites and diseases that a home bin won't kill, and Garden Organic lists both as things not to compost.
Sources
- Royal Horticultural Society. Composting.
- Garden Organic. What can I compost?
- Garden Organic (2018). Are you composting your tea bags?
- University of Plymouth (28 May 2024). Study suggests biodegradable teabags don't readily deteriorate in the environment.
- Purkiss, D., Allison, A.L., Lorencatto, F., Michie, S. and Miodownik, M. (2022). The Big Compost Experiment. Frontiers in Sustainability, 3.
- GOV.UK. Simpler Recycling: household recycling in England.