Compost is made by combining organic waste than provides nitrogen and/or carbon. The advice to make compost from waste that is green (provides nitrogen) and brown (provides carbon) is a bit confusing when manure contains a lot of nitrogen, but most of it is brown. When suitable dampened materials are combined in a heap that has contact with the soil, heat is generated and millions of aerobic bacteria get to work transforming the fuel into a compost-making factory.
Good Fuels
- Manure from animals that eat grass (lots of nitrogen)
- Chicken manure (lots of nitrogen)
- Weeds without seed heads (nitrogen and carbon)
- Lawn cuttings that have wilted (nitrogen and carbon)
- Green prunings – shredded (nitrogen and carbon)
- Raw vegetables and fruit – chopped for fast break down (nitrogen and carbon)
- Uncooked kitchen waste – including tea bags and coffee grounds (nitrogen and carbon)
- Old plants – chopped for fast break down (nitrogen and carbon)
- Bedding straw for animals that eat grass or seeds (lots of nitrogen and carbon)
- Straw and hay (lots of carbon)
- Cardboard boxes and egg cartons – shredded (carbon)
- Undyed wool, feathers and hair (nitrogen and carbon)
In Small Amounts
- Newspaper and waste paper – separate sheets crumpled or roughly shredded (carbon)
- Woody prunings – shredded (carbon)
- Wood shavings – (very slow to break down and tie up a lot of nitrogen)
- Seaweed – well-washed (helps factory work faster)
- Herbs – comfrey, yarrow and chamomile (help factory work faster)
- Egg shells – crumbled (keep compost smelling sweet and earthy)
Do Not Add
- Plastic or foil containers, wrapping or disposable nappies
- Fruit or vegetables that have been attacked by fruit fly or codling moth (larvae can pupate in factory)
- Plants with diseases
- Cat, dog or human faeces* (these can spread diseases through compost)
- Rats or mice* (can spread diseases through compost)
- Grey water (upsets pH balance and slows process)
- Soil – makes compost heavy and harder to turn (amount clinging to weed roots is sufficient)
- Earthworms – the initial heat will kill them. Earthworms know when to move into a compost factory.
- Synthetic fertilisers (delays process and deters earthworms)
If you only have small quantities of organic waste to recycle, a worm farm would be a better solution. See Compost Worm Farm.
For information on how compost makes garden soil healthy, see Compost.
** Cat and dog faeces, and vermin, can be composted anaerobically in a small pit or container, but this compost should not be added to garden beds.