Composting Eco-Challenge

Small Actions.
Big Change.

TASK: Create a mini compost bin that you can use for your backyard, campus or company garden to improve the structure and health of your soil!


  • 1 empty litre (soda) bottle

  • Sharp knife

  • Nail

  • Shredded newspaper

  • Dirt (not potting soil, use dirt from outside)

  • Compost materials (grass clippings, vegetable scraps)

  • A small handful of dead leaves

  • Flat dish to hold composter

  • Spray bottle with water


  1. Rinse the bottle and peel off the label.

  2. Cut off the top of the bottle, approximately 1-2" inches below the neck of the bottle. Set the top aside.

  3. Use a nail to punch 8 to 10 small air and drainage holes along the sides and bottom of the bottle.

  4. Put the bottle on the tray. Put some dirt, shredded newspaper and old leaves inside the composter. This is your compost starter.

  5. Use the spray bottle to wet the compost starter.

  6.  You're ready to add to your compost! (Try grass clippings, vegetable scraps, coffee grounds, or eggshells, but do not add dairy or meat.)

  7. Turn the bottle top upside down and place it in the open top of the bottle. It will act like a funnel  Use your compost by adding 1-2 inches of compost soil into the top 3-5 inches of soil in your garden!

  8. Add a little water each day to keep the contents damp.

  9. Place your compost bin in a spot where sunlight can reach it. Cover the top of your compost with a kitchen towel when not in use.

  10. Every few days stir the compost and make sure to keep the contents damp. As your compost breaks down, you can add more kitchen scraps or plant litter, as well as some more soil from outside to mix in.


  • Snap a picture of your compost bin OR film a 30-sec video that shows us how you used your compost! Be sure to make your submissions in the WePlanet app in Eco-Submissions 
  • Compost material must include food waste like vegetable scraps etc.
  • Provide your full name and contact information (phone number, email address etc.) when submitting (update your profile to include these details). If submitting on behalf of a club or organization please include the organisation's name. 

DEADLINE: Decemeber 31st, 2023 11:55pm

WINNER: All submissions will be placed in the Eco-Warriors Section.  All submissions will be entered into a raffle. 

PRIZE: $50USD Amazon Gift Card

*Do you need help with your composting?  Feel free to reach out to Siel Environmental and take part in a Composting Class!