Waste in landfill is so crushed that any decomposition is anaerobic and produces methane that contributes to global warming. Compost bins provide the ideal environment for microscopic organisms like bacteria to break down the organic material we throw away. These organisms also need warmth, moisture and air, so the bins should be sited where they’ll get some sun and the contents watered lightly if dry, and turned now and again (every two or three weeks for us) with a fork to ensure a good supply of air. Also, consider the route from kitchen to composter — an easy walk will make it less like a chore.
The key is to maintain a mixture of items, with a balance of browns (flowers, woody stems, cardboard) and greens (grass, kitchen waste). Almost every meal contributes something to the compost but it would be worth us doing it just for the vast quantities of tea bags and coffee grounds we generate.
We keep it in a lidded ceramic crock on the counter. The crock has a carbon filter in the lid to remove smells, but when we first used a bowl with no lid, we never noticed a smell, so I don’t think we will be buying many filters.
The smaller the pieces you add to the composter, the speedier the decomposition. It can take from six to nine months for the compost to resemble dark soil and smell sweet and earthly, when it is ready to go on the garden.
At a time when councils are considering charging residents according to their levels of waste, composting is a cheap and very effective way of making a positive contribution to the environment. And it is so simple, it should be compulsory for all garden owners.
Dr Zoe Kelion is a GP in London