Close this search box.

Compost Cake


  1. Choose where you will create your permanent compost area — this needs to be at least 1m2.
  2. Ask young people to share what they already know about decomposition and making compost, and share information with them if necessary:
    • Materials that have been alive will decompose
    • Decomposed matter can provide nutrients fornew plants to grow
    • This nutrient cycle is helped along by fungi, minibeasts and other organisms
  3. Demonstrate building a miniature compost cake with samples of ‘browns’ (carbon-rich materials such as dead plants, leaves, or straw), ‘greens’ (nitrogen-rich materials such as grass clippings, fresh plant matter, or food scraps), and soil or old compost. Stress the importance of the size, ingredients, and moisture level.
  4. Use forks to loosen the ground where the pile will be. Divide into teams Browns, Greens, and Soil, with one person the waterer. Begin to build your pile with a layer of stalky brown material to allow drainage. Rotate teams, layering browns, greens, and soil repeatedly until the pile is at least 1m tall. Brown and green layers should be 10-15 cm thick; soil layers should be 3-5 cm thick. The waterer needs to water each layer as it is added to the pile.
  5. As you build up the pile, make sure you keep it in shape and keep the corners as square as possible so that the pile doesn’t collapse and lose its heat.

Take it further

If you can, record the temperature of your compost cake each week – over time it should heat up to around 70°C and then start to cool down – discuss how the heat is being produced by the activity of microorganisms breaking down the materials in the pile. You could look at samples of the compost with a lens or microscope.

When you have usable compost, you could use this to grow your own food to share or use on camp.

This activity has been adapted from resources created by Kiss The Ground — visit their website for more information and activities about the carbon cycle and improving the soil. You’ll need an outdoor space like a community allotment or garden to do this in — ideally one you can return to throughout the year.

Resources Required

Wheelbarrow, Garden spades/forks, Compostable materials, Peat-free compost, Thermometer


Share this Activity:

Our website uses cookies. By continuing to browse the site you agree to our cookie notice

Skip to content