Compost heap
An impressive compost heap

Gardeners are privileged to witness miracles on a daily basis – seeds germinating, buds unfurling and bees pollinating flowers. No less miraculous are the quiet miracles that take place in the compost heap, where tiny organisms turn waste products into compost, allowing the cycle of life to begin again.

To the uninitiated, the composting process looks complicated. Television gardeners often do nothing to dispel this myth, with sprawling heaps and endless vigour that allows them to turn their compost almost daily. But composting is a natural process that happens everywhere, daily, without interference. With a little help from us it can happen in our gardens almost as effortlessly.

Many gardeners’ first encounter with composting is with a plastic composter. Plastic composters are fantastic, but are not without their faults. Their plastic walls catch the sun and keep heat in, speeding the composting process, but are unattractive and often relegated to shady areas of the garden. They are easily assembled, but their steep sides and small openings make it hard to get a spade inside to turn the compost or extract it. A steady diet of kitchen waste and grass cuttings guarantees a slimy, smelly mess and many would-be composters must be discouraged by their first attempts.

CAT cold composting
The Centre for Alternative Technology has developed a cold composting process that is ideal for use in small gardens, and for plastic composters. This ‘high fibre’ method involves mixing kitchen and garden waste with crumpled paper and torn cardboard. Waste is added to the heap as and when it is available, creating a continuous composting process. The compost is never turned and will not heat up enough to kill weed seeds and plant diseases, but produces high quality compost with minimal effort.

  • Add crumpled waste paper and torn cardboard to the compost heap with kitchen and garden waste as they become available. The exact ratio doesn’t matter – the idea is to avoid thick layers of any one material.
  • There’s no need to turn the heap.
  • Don’t add diseased plant material or seeding weeds.
  • The compost will be ready to use within a couple of months in the summer, but will take longer in cold weather.
  • If you have access to the bottom of the heap then you can extract finished compost as and when you need it.

Worm composting
A worm composter is ideal for small gardens. Composting worms eat their way through much of our kitchen waste, producing a small amount of very rich compost and a large amount of liquid plant feed. Many people are squeamish about worms, but once they are settled into the wormery you rarely encounter them. Children have no such qualms and wormeries are an ideal introduction to composting for them.

Worm composters are living environments and need some care and protection. Worms freeze if exposed to cold weather, and drown if the wormery is not properly drained, but when properly managed a worm composter easily disposes of a family’s kitchen waste.

Bokashi bins
Compost heaps and wormeries will not deal with meat, dairy products or large amounts of cooked food. One solution is to invest in a Bokashi system, also known as EM (Effective Microorganism) composting. Food waste is added to airtight buckets with a sprinkling of EM-enriched bran. The microorganisms effectively pickle the waste and when you remove it from the bucket it will look exactly the same as when it went in – and smell strongly of vinegar. When added to a compost heap at this stage, the waste rapidly decomposes – with no danger of attracting rodents.

This makes Bokashi buckets ideal for collecting food waste from flats for community composting, but requires a continuous supply of Bokashi bran. The buckets used can be quite expensive.

Green cones
An alternative for people with access to an area of soil is a green cone. The green cone has a basket that is placed in a hole in the soil. The cone itself fits on top and should exclude vermin. A green cone can deal with any sort of kitchen waste, and also with animal faeces, but is not recommended for use with garden waste. The basket underneath the cone is emptied no more than once a year.

This article first appeared in Country Gardener in March 2008.