Anything that was once living will compost, but some items are best avoided. Meat, dairy and cooked food can attract vermin and should not be home-composted.

Some things, like grass mowings and soft young weeds, rot quickly. They work as 'activators', getting the composting started, but on their own will decay to a smelly mess.

Older and tougher plant material is slower to rot but gives body to the finished compost - and usually makes up the bulk of a compost heap. Woody items decay very slowly; they are best chopped or shredded first, where appropriate.

For best results, use a mixture of types of ingredient.
The right balance is something you learn by experience, but a rough guide is to use equal amounts by volume of greens and browns (see below).

Compost ingredients

'Greens' (nitrogen-rich ingredients)

• Grass cuttings
• Young weeds
• Nettles (not roots)
• Comfrey leaves
• Urine (ideally diluted 20:1)
• Uncooked fruit and vegetable peelings
• Tea bags, leaves and coffee grounds
• Soft green prunings
• Animal manure from herbivores eg cows and horses
• Poultry manure

'Browns' (carbon-rich ingredients)

• Cardboard eg cereal packets, toilet roll tubes and egg boxes
• Waste paper and junk mail, including shredded confidential waste
• Paper towels & bags
• Newspapers and glossy magazines (although it is better for the environment to send them for recycling)
• Bedding (hay, straw, shredded paper, wood shavings) from vegetarian pets eg rabbits and guinea pigs
• Tough hedge clippings
• Woody prunings
• Old bedding plants
• Bracken
• Sawdust
• Wood shavings
• Straw
• Autumn leaves (but use to make leafmould if quantities are large)

Other compostable items

• Wood ash, in moderation
• Hair, nail clippings
• Egg shells
• Natural fibres eg wool and cotton

Do NOT compost

• Meat, fish, dairy products or cooked food
• Coal & coke ash
• Cat litter
• Dog faeces
• Disposable nappies

Next - How do I make my compost?