Composting and worm farming

Effective composting requires a good balance of carbon-rich and nitrogen-rich materials. Think of carbon-rich materials as “brown things” (such as dried leaves, paper, and timber/bark pieces) and nitrogen-rich materials as “green things” (such as food scraps and grass).

Items that can be composted include:

• Fruit and vegetable scraps
• Newspaper and shredded paper
• Grass clippings
• Dead flowers
• Leaves and twigs
• Egg shells (crushed)
• Ground coffee
• Tea bags and leaves
• Animal and human hair
• Old potting mix

There are a few things that can attract unwelcomed guests, such as mice and flies, to your compost. Make sure you don't add any of the following to your compost:

• Meat
• Seafood
• Dairy products
• Oils and fats
• Pet faeces
• Large amounts of carbohydrates, such as bread, rice and pasta. These high protein items are nitrogen-rich and can be added to your compost in very small volumes in combination with carbon-rich items, like shredded paper and dried leaves.

Follow these three simple steps to have a healthy compost pile:

• Balance nitrogen and carbon content: Roughly ½ of "green" materials and ½ of "brown" materials.
• Provide good aeration: Mix your compost at least once a week.
• Keep it moist: Place a hessian sack or damp old cloth or T-shirt over the pile to prevent water evaporation.

The bin should be placed on bare soil to allow for sufficient drainage in a partially sunny spot of your garden – preferably somewhere cool in summer and warm in winter with good air circulation. It is good to keep your bin away from the house and neighbours, but in a convenient location to empty your food scraps on a regular basis.

Keep your compost covered to stop unwanted pests making a home in your compost.

1. Layer the bottom of your bin or a heap with a 10–15cm layer of coarse materials from your garden. Small sticks or mulch are perfect.
2. Add a layer of finer carbon-rich materials from your garden, e.g. dried leaves.
3. Optional: Add a 1–3 cm of soil to help kick-start the composting process.
4. Add a layer of nitrogen-rich materials to the pile, e.g. kitchen scraps, grass and flowers.
5. Add another layer of carbon-rich materials to the top.
6. Water each layer to ensure all materials are moist.
7. Cover the pile with a hessian sack, damp cloth or newspaper to keep the compost moist.
8. Aerate your bin after 1 week by mixing its content.

• Use sifted compost as potting mix and seed raising mix. Woody leftovers can be used for mulch, or re-added to the compost bin to break down further.
• Add a 2 to 5 cm layer around the drip line of trees. Spread thinly once or twice a year as a top dressing for lawns. Apply twice a year to Australian natives.

Council provides a range of options to start your composting journey!

Residents can order a discounted compost bin and aerator through the Compost Revolution program. Everything you need to get started will be delivered to you. Take the tutorial, do the quiz, and order your composting equipment. Please choose carefully as there are no refunds or exchanges.

A wide range of compost bins are also available from local nurseries and garden centres.

This project is a NSW Department of Planning, Industry and Environment, Waste Less, Recycle More initiative funded from the waste levy.

See the Easy Composting Guide  (PDF 1.1MB) produced by the NSW Environment Protection Authority (EPA) for more information on composting.

A worm farm consists of two or three trays.

The bottom tray collects liquid fertiliser, which is high in nutrients and can be diluted to a weak tea colour to use on your plants.

The other trays are the 'working trays' where the worms live, breed and work, turning your kitchen scraps into rich castings which can be used as an excellent soil conditioner.

The following items can go into your worm farm:

• Fruit and vegetable scraps (see “bad foods for worms” below for exceptions)
• Egg shells (ground or crushed)
• Coffee grounds
• Tea bags and leaves
• Animal and human hair
• Vacuum cleaner dust
• Shredded paper (small amounts)
• Cooked leftover food, such as pasta and rice (very small amounts)
• Cut flowers

There are foods that won’t break down and could make your farm start smelling or attract unwanted guests such as mice and cockroaches.

The following items cannot go into your worm farm:

• Garden clippings, prunings, leaves, etc.
• Citrus fruits
• Onion and garlic peel
• Chilli
• Meat and seafood
• Dairy products
• Tofu
• Bones
• Oils and fats

When getting started with a worm farm:

• Create a 10–15cm deep layer of 'bedding' for the worm farm using a mixture of shredded newspaper, leaves and finished moist compost or soil (or fibre material supplied with the worm farm). Add the worms to the surface of the bedding and cover the bin with a natural material (e.g. moist newspaper or hessian bag).
• Leave the worms for a few days to get used to their new home before adding any food.
• Make sure you start with small amounts of food, gradually increasing it week by week.
• Place your worm farm somewhere convenient where it can be easily accessed.
• Keep your worm farm in a shaded spot outside or indoors – worms don't like extreme temperatures.
• Keep your worm farm moist – cover the worm bed with a hessian bag, damp newspaper or old T-shirt.
• Add food to worm farm in small pieces. Worms are very efficient and can process the equivalent of their body weight each day, but smaller scraps will be processed faster.
• Make sure the environment is not too acidic – ground egg shells help to regulate the pH inside the worm farm.

Worms create a material called 'castings'. This is basically the organic material that has been digested by the worms.

Worm castings contain many beneficial bacteria and enzymes that can help in growing healthier plants, improving soil texture, and providing water-soluble nutrients to the plants. Worm castings have the texture of coarse coffee grounds or peat moss.

1. Empty the worms and bedding onto a surface and scrape the castings from the outside as the worms move towards the centre.
2. Use the ball of worms for a new bedding -or-
3. Move all of the castings to one side of the bin, and add fresh bedding to the empty side. Many of the worms will migrate to the fresh bedding in a few days.

Once you have your castings, they can be used as plant food (add a 3–6cm layer around plants and cover with mulch) or to improve the quality of a potting mix (add 10–20% castings to a poor potting mix).

Worm farms also create liquid castings in the bottom tray, which can be collected and diluted with water (to a weak tea colour) to make a high-nutrient liquid fertiliser for your pot plants.

The Green Living Centre runs worm farming workshops several times a year. You'll learn everything you need to know to set up and maintain your own worm farm.

Residents can order a discounted worm farm and worms through the Compost Revolution program. Everything you need to get started will be delivered to you. Take the tutorial, do the quiz, and order your worm farming equipment. Please choose carefully as there are no refunds or exchanges.

This project is a NSW Department of Planning, Industry and Environment, Waste Less, Recycle More initiative funded from the waste levy.