Composting and Compost Bins
Composting is the systematic breaking down of organic material, for use mostly within the gardening environment. Recycling organic waste into the garden, in the form of compost, decreases the garden’s need for water and fertiliser.
What can I compost?
Compost can be made from any organic material thrown together in a pile and left to break down. However, there are ideal circumstances that can be easily reproduced to achieve the best results in the shortest amount of time. The ideal mix for compost uses approximately the same amount of 'green' and 'brown' material. Green includes 'alive' material such as fruit and vegetable scraps, fresh grass clippings, fresh leaves, tree and rose prunings, weeds and fresh animal manure. Brown includes 'dried' material such as shredded paper, dried leaves, woodchips, sawdust and straw. You can also add activators, like lime, to give your compost a kick-start. Activators and additives are available from garden centres and hardware stores. Or if you like herbs, comfrey is an excellent activator.
Composting works best if all the material is shredded or chopped as small as possible. It is also important to keep the mixture damp, which also minimises any airborne spores or bacteria.
Do not add meat, dairy products or bones to your compost.
Composting bins - longer term, smaller quantities
Smaller properties and units can successfully compost using bins or tumbers. Many people prefer bins, as this keeps everything looking neat and it is easy to add scraps and water when required.
Compost bins come in various shapes and sizes, and you will find many types at your local garden or hardware store. When purchasing a bin ensure it is fly and vermin proof.
Enclosure method - larger quantities, quicker results
If you have a grassed area, you have a ready supply of lawn clippings. Your garden will benefit if you use a three or five 'bin' method, which utilises larger piles in small enclosures, for optimum heat and microbe activitiy. Enclosures can be made from timber, bricks, chicken wire, corrugated iron, pieces of lattice - use your imagination and available resources.
In the first enclosure, layer greens and browns in alternative layers, about 10cm thick. Moisten (don't drench) with a spray from the hose or watering can. Additives and activators can be included to assist the material to break down, but are not entirely necessary. Cover in a layer of straw or wood chips to prevent it from drying out.
After one week in summer, or two weeks in the cooler months, move the entire pile into the next enclosure with a shovel or pitch fork. As the pile is turned into the next enclosure, the layers will be mixed thoroughly. Again cover in a layer of straw or wood chips.
You can then start a new compost mix in the first enclosure. After another week, turn each pile into the next enclosure. Make sure each pile is covered in woodchips, sawdust, straw or hessian.
Once the compost has remained in the last enclosure for a week, it should be ready to use on the garden, providing nutrients and helping to retain moisture.
Open piles of grass clippings or mulched green waste
Compost can be made in open heaps, but ideally it should be covered in a thick layer of straw or wood chips, or alternatively with a plastic sheet or hessian, to prevent it from drying out too much. Compost that is left to sit undisturbed will take quite a while to break down, up to six months. However if you turn compost regularly, about once a week, and keep it damp, it heats quickly and evenly and breaks down within about 12 weeks.
If you would like further information, the following books are available from the City of Armadale Libraries:
- 'Green Home Composting - 16 ways to compost or worm farm' by Alan Windust
- 'Composting' by CSIRO Australia
- 'Introduction to Permaculture' by Bill Mollison