How to Have a Pest-Free Backyard Compost

Composting is an excellent way to recycle organic garden and kitchen waste to enrich your garden's soil. However, it can sometimes attract unwanted pests which can discourage many folks from even trying. By following these general guidelines, you can enjoy the benefits of composting without the hassle of unwanted pests.

Common Compost Pests

• Rodents (Rats/Mice)

  • Attracted to warmth, shelter and potential food sources.

  • Deterred by secure bins and regular disturbance.

• Raccoons

  • Drawn to food scraps

  • Prevented by locking lids and avoiding composting meat and dairy.

• Fruit Flies

  • Attracted to exposed fruit scraps

  • Managed by covering food waste with brown materials.
    

    

    A pest-free 3 bin design (Source: themeshcompany.com)

Pest-Free Compost Practises

Select the Right Compost Bin

Choosing an appropriate compost bin is crucial in deterring pests.

• Features to Consider:

  • Locking Lids: Bins with secure, locking or heavy lids prevent animals like raccoons from accessing the contents.

  • Solid Bases or Mesh Linings: Bins with solid bottoms or those lined with ¼-inch hardware cloth (also known as wire mesh) stop rodents from burrowing in.
    

Optimal Bin Placement

The location of your compost bin can influence pest activity.

• Placement Tips:

  • Open Areas: Position your bin away from buildings and fences. Placing it in an open space makes pests feel more exposed and less likely to approach.

  • Avoid Dense Vegetation: Keeping the area around the bin clear reduces hiding spots for pests.

Appropriate Compost Materials

What you add to your compost significantly affects pest attraction.

• Compostable Items:

  • Fruit and vegetable scraps

  • Coffee grounds

  • Eggshells

  • Yard waste

• Avoid Adding:

  • Meat, dairy, grains, oils, or bones.

Keep the Compost Hot

Thermophilic temperatures decompose quicker and deter pests from burrowing.

• How to Keep it Hot:

  • The Ideal Thermophilic Temperature: Between 54°C and 71°C or 130°F and 160°F.

  • Turn Your Compost: Disturbs pests and increases the inner temperature.

    TIP: Buy a compost thermometer to keep track of its internal temperature which will indicate when it is best to turn your pile.

Maintain Proper Compost Balance

A well-balanced compost pile decomposes efficiently and is less appealing to pests.

• Maintenance Practices:

  • Regular Aeration: Turning your compost frequently not only speeds up decomposition but also disturbs any potential nesting sites, deterring pests from settling in.

  • Cover Food Scraps: Always cover fresh food waste with a layer of brown materials like leaves or shredded paper to minimize odours that attract pests.

Regular Monitoring

Keeping an eye on your compost system will help in early detection of pest issues.

• Inspection Routine:

  • Check for Signs of Pests: Look for burrows, droppings, or chewed areas around the bin.

  • Ensure Structural Integrity: Regularly inspect the bin for any gaps or damage that could allow pest entry.

For more detailed information on having a pest-free compost, refer to the Compost Education Centre's Factsheet on Vermin Resistance.