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Mulcher: Organic material is emptied into a shredder on arrival at the worm farm, with water added to the material as it is fed through the machine. Photo by Amy Mosig.

Your food scraps are good for another meal. With the added help of compost worms, your leftovers can keep coming back to your dinner plate.

We rely on natural resources for everything we do and have. This includes our food. We take materials from nature, use them, sometimes we change them, and then we dispose of what remains.

Nature has one of the best methods of disposal. Organic matter, such as food and paper, is broken down through decomposition, a naturally occurring process involving bacteria. The decomposed material is rich in nutrients and can be recycled to help other things grow. In this way, nature closes the loop: turning resources back into resources - wasting nothing.

Most food scraps and some waste paper can be recycled through composting. Compost worms help to speed up this process. They eat the bacteria that live on the organic scraps. The waste material they produce is called castings. It is rich in nutrients and can be used as fertiliser, either as a crumbly soil-like product, or through worm juice - a water-based solution that can be sprayed or poured onto soil. These fertilisers are organic.

If you compost at home or at school, you can use the compost or worm castings for your garden. You can turn tonight's lunch or dinner scraps into another meal if you grow your own vegetables, herbs or fruit.

As well as providing a rich fertiliser, composting redirects organic matter so it does not have to be transported to rubbish dumps or landfill.

Five bed castings: Richard Hobbs lifts the cover on one of the long beds of mulched material on which the worms feed. Photo by Amy Mosig.

Australia disposes of 620kg of domestic waste per person each year. Over 95 per cent of solid waste is disposed of to landfill, of which construction and demolition of buildings contributes between 40 and 50 per cent. Landfill sites take up land that could be used for other purposes, including natural processes like providing habitat for different species.

Landfill sites also cost money to establish and to operate. Reducing organic waste to landfill also reduces greenhouse gases (methane) from rotting vegetation. If landfill sites are not managed well, they can cause environmental problems. If they are located a long way from the places that generate the waste, it also costs money and produces greenhouse gas emissions from vehicles to transport the waste to the site.

As well as reducing waste, composting can generate business and create jobs. Some local councils have green waste collections and recycle this material into mulch for sale to reduce the need to water gardens. Councils also sell worm farms and compost bins cheaply because composting helps reduce the rubbish that goes to landfill and that saves money as well as resources. Check with your council about what it offers.

Composting can also generate business through worm farms. They collect waste, use the worms to compost it, and sell the castings. They might also breed worms to sell.

So composting makes good sense for lots of reasons.

Each bed contains tens of thousands of worms. Photo by John Armstead.

What you can do

Sort your rubbish. Put the organic material out for composting. You can use a small bin in the kitchen and transfer this to a larger bin, as you need. Or you can take your scraps to the big bin after each meal.

If you live in a unit or townhouse, you can use a small composting bin, or buy a small, portable worm farm and feed the scraps to the worms.

Use worm castings and worm juice. These can be made with your own worm farm or you can buy them commercially.

To get the best from composting, you need to follow some simple rules. More information on making your own compost.