What can you put in your compost bin? The complete list of accepted and refused waste

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“Can this go in the compost?” It is the question we ask ourselves at the kitchen caddy, peeling or tissue in hand. Good news: a garden compost bin accepts a very wide variety of waste, far more than a wormery. There are still a few exclusions you need to know about, and a handful of items to add with common sense.

Here is the complete list, sorted into four groups: what goes in without hesitation, what goes in sparingly, what never goes in, and the items that are up for debate.

Yes, without hesitation: kitchen waste

The kitchen provides most of the everyday additions. This waste is moist and rich in nitrogen: these are the materials known as “greens”.

• Fruit and vegetable peelings and tops, raw or cooked, as well as damaged fruit and vegetables.
• Coffee grounds and paper filters, paper tea bags (remove the staple if there is one).
• Plant-based leftovers: rice, pasta, cooked vegetables, in reasonable quantities.
• Eggshells, preferably crushed.
• Wilted flowers from bouquets and houseplants.

Did you know?

Eggshells and seashells hardly break down at all in a household compost bin. That does not make them useless: they aerate the mix and gradually release minerals. Finding them whole when you harvest your compost is therefore perfectly normal.

Yes, without hesitation: garden waste

The garden supplies both green materials (grass cuttings, young shoots) and dry materials, known as “browns”, which are essential for giving the compost structure.

• Grass cuttings, never in a thick layer and always mixed with dry material.
• Dead leaves, preferably shredded or run over with the mower.
• Hedge trimmings and small branches, cut up or shredded.
• Straw, bark, wilted flowers, end-of-season vegetable garden residues (tomato plants, bean haulms…).
• Weeds pulled up before they go to seed.

The garden often produces more waste than the kitchen: we explain how to manage large volumes in our guide Green garden waste.

Yes, without hesitation: some household waste

It is easy to overlook, but several kinds of household waste make excellent brown materials, invaluable for balancing out peelings.

• Paper tissues and kitchen roll (without cleaning products).
• Unprinted brown cardboard, torn into pieces: egg boxes, kitchen roll tubes, packaging boxes without tape.
• Newspaper, in small quantities and scrunched up or shredded.
• Sawdust and shavings from untreated wood, never from treated, painted or varnished wood.
• Cold wood ash, in small quantities: it is very alkaline, so a handful from time to time is enough.
• Houseplants that have wilted or reached the end of their life.

Sparingly or in small pieces

This waste is compostable, but it needs a little attention, either because it breaks down slowly or because it can attract animals.

• Bread, dairy products, cheese rinds: accepted, but in small quantities and buried in the centre of the heap so as not to attract rodents.
• Citrus fruit: yes, in pieces and in the normal quantities of a household.
• Hard or woody waste: cabbage stalks, fruit stones, thick stems and branches. They take a very long time to break down if they are not cut up or shredded first.
• Large quantities of a single type of waste: a whole bucket of grass cuttings or leaves in one go throws the mix off balance. It is better to store it alongside and add it little by little.

Willy's tip

The smaller a piece of waste is cut, the more surface it offers to micro-organisms and the faster it breaks down. A quick chop of cabbage stalks and melon rinds as you throw them away saves a great deal of time.

No: the red list

This waste has no place in a compost bin, either because it does not break down, or because it pollutes the compost or poses a health risk.

• Plastics of all kinds, including so-called “biodegradable” bags and plastics: they must not go in a home compost bin.
• “Compostable” tableware and bags: they are designed for industrial composting facilities, where the temperature rises far higher than in a garden compost bin.
• Disposable nappies, wipes, vacuum cleaner bag contents.
• Glass, metal, synthetic fabrics, glossy paper and fruit stickers.
• Treated, painted or varnished wood, and chemicals (used engine oil, solvents…), which go to the household waste recycling centre.
• Cat litter and dog or cat faeces, which can transmit diseases.
• Diseased plants and weeds that have gone to seed: a household compost bin does not get hot enough to destroy pathogens or seeds.

Key points

A simple rule for doubtful cases: untreated plant-based waste that would break down on its own in nature is very likely to be fine for the compost bin. For anything that comes from an animal, check the list.

The items that are up for debate

Meat and fish, bones, large quantities of citrus fruit, bedding from herbivorous pets, invasive perennials: opinions differ depending on the source and the type of compost bin. We have gathered these cases, with our position on each one, in a dedicated guide: Citrus fruit, meat, bread, pet bedding, weeds: the waste that is up for debate.

For leftovers that the compost bin struggles to digest (meat, fish, dishes in sauce), there is a complementary solution: bokashi fermentation, which prepares them before they go into the compost bin or the soil.

Compost bin or wormery: not quite the same list

If you also have a wormery, do not mix up the two lists. Compost worms are more sensitive: they do not like large amounts of grass cuttings or branches, and citrus fruit and the onion family should be limited for them. A garden compost bin, on the other hand, accepts much more waste and in larger volumes. For worms, see our guide What can you feed earthworms?

The handy reminder to keep next to the caddy

So that the whole family can sort without hesitation, here is the short version, to copy onto a label or stick on the cupboard door:

• Yes: peelings, damaged fruit and vegetables, coffee grounds and filters, tea, eggshells, wilted flowers, grass cuttings in a thin layer, leaves, small shredded trimmings, kitchen roll, tissues, brown cardboard, sawdust from untreated wood.
• A little, cut small and buried: bread, dairy products, cheese, citrus fruit, leftovers, cold wood ash.
• No: plastics, even “biodegradable” ones, compostable tableware, nappies, wipes, glass, metal, fabrics, treated or painted wood, chemicals, cat litter, dog or cat faeces, diseased plants, weeds gone to seed.

In the kitchen, a caddy with a lid saves daily trips to the garden and keeps fruit flies away. The Kaylis 7L compost bin or the Maze 9L compost bin keep peelings close to hand between trips to the garden. Also remember to keep a supply of dry material (leaves, cardboard, shredded material) next to the compost bin: for every bucket of kitchen waste, add some browns. We explain why in our guide Green and brown materials.

In summary

Almost everything from the kitchen and garden can go in the compost bin: peelings, coffee grounds, shells, grass cuttings, leaves, shredded trimmings, kitchen roll and brown cardboard. Bread, dairy products and citrus fruit can go in in small quantities. Plastics (even “biodegradable” ones), treated products, cat litter and diseased plants remain excluded. If in doubt, ask yourself whether the waste is plant-based, untreated and would break down on its own in nature, and cut it into small pieces.

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