Composting is a good way to recycle your kitchen and garden waste into nutritious food for plants. Try this activity to turn waste into earthy goodness!

Gardening scraps, gloves and other equipment on a wooden deck

You will need

  • “Green” materials such as fruit and veggie scraps, loose tea leaves, eggshells, grass clippings, plant cuttings, weeds, old flowers
  • “Brown materials” such as paper, cardboard, dry leaves, sticks, straw, untreated wood or sawdust
  • Garden secateurs
  • Gardening gloves
  • A large plastic pot or bucket with drainage holes
  • Garden soil
  • Watering can


This activity involves going outside, cutting with secateurs, and handling kitchen and garden waste.

Be sun-smart and ask an adult for help when collecting and cutting garden materials. Wear gloves when handling kitchen and garden waste, and do not touch any diseased plants.

Do not use any oils, meats or treated materials for composting. Wash hands thoroughly after this activity.

outdoor hazard icon
sharp hazard icon
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What to do

  1. Put on your gardening gloves and gather some “brown materials” such as twigs, dry leaves, unused paper, cardboard, or hay. Then, cut or tear your brown materials into smaller bits.

  2. Place about 2 to 3 centimetres of your “brown materials” into the bottom of your plastic pot or bucket.

    Black plastic pot containing dry sticks and torn paper.
  3. Gather some “green materials”, such as kitchen fruit and veggie scraps, loose tea leaves, eggshells, garden cuttings, weeds or old flowers. Cut or tear the green materials into small bits.

  4. Place about 2 to 3 centimetres of your “green materials” on top of the brown materials in your plastic pot or bucket.

  5. Repeat steps 1 to 4, creating a browns and greens “sandwich” until you fill your plastic pot or bucket about 80% full. Make sure your final layer is a browns layer.

  6. Now, dig up some garden soil from your backyard. Fill your pot or bucket to the brim with the garden soil.

  7. Place your filled pot or bucket in an unused patch of your garden. Water your pot or bucket until water starts to seep out of the drainage holes. Then, leave your pot or bucket in its place, watering it when it dries out. After a few months, you will get a pile of compost!

What’s happening?

A good compost mix has 6 main ingredients: greens, browns, microorganisms, oxygen, water and patience!

Greens contain lots of nitrogen, while browns are rich in carbon. When greens are mixed with browns, microorganisms such as fungi and bacteria on the materials can access the carbon for energy and nitrogen for growth. As the microorganisms chomp away at the carbon and nitrogen compounds, they help to break down the browns and greens. This process generates heat, so you might see steam coming from your compost mix. Garden soils also have lots of microorganisms in them, so topping your mix with soil can help to speed up the composting process.

Adding chunky brown materials to the bottom of the pot introduces air, which contains oxygen. Oxygen in the air will react with the carbon and nitrogen compounds in the mix and speed up the composting process.

Giving your compost a bit of water helps to keep the chemical reactions going, while keeping the compost at a good temperature for the microorganisms. Water will also feed the microorganisms and help them to work efficiently. But adding too much water can make a compost mix too wet and stinky, so don’t overdo it!

Depending on your climate, the chemical reactions in the compost can take up to a year to finish converting the food and garden waste into nutritious compost. But you’ll know it’s ready when all the materials have turned into bits of earthy-smelling, dark brown goodness!

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