How Paper Bags Can Help with Backyard Composting in Australia

The Australian government advocates for backyard composting to help minimise the mounting piles of rubbish in landfills and control the growing pollution in the country. 

Learn how to include paper bags in your backyard compost with this blog post.

What is backyard composting?

Backyard composting is when you make a pit using the space outside your home to decompose food scraps and other organic material. 

Composting involves the natural breakdown of organic matter over time. Various organisms - bacteria, fungi, worms and other insects act as decomposition agents, breaking down the materials into nutrients for the soil. 

The process of composting turns the soil into a nutrient-dense ground, otherwise known as “black gold.” It will be fertile enough to grow vegetables and herbs. Some communities create backyard compost for all residents so that they can have a shared community garden where everyone can have access to the crops they grow. 

Backyard Composting in Australia

Bin audits conducted by the Department of Agriculture, Water and Environment showed that 40 to 60% of the waste being sent to landfills are organic waste products that can be used for backyard composting or sent to farmers to improve the quality of agricultural land. 

This causes a problem because organic waste that ends up in the landfill is buried and decomposes anaerobically, meaning without air. Anaerobic decomposition adds 3% to Australia’s annual greenhouse gas (GHG) emissions.

There is a huge need for Australians to practice backyard composting because a 2021 FIAL study showed that around 830,000 tonnes of food waste from restaurants, cafes and hotels go to landfills but only 131,000 tonnes are commercially composted. 

By practising backyard composting, we can increase the number of food waste being aerobically decomposed, reduce air pollution and build a sustainable food resource. 

What are the pillars of composting?

There are four basic requirements for composting - water, oxygen, nitrogen-rich matter and carbon-rich matter. Water provides sustenance to the microbes working to decompose the biodegradable elements. 

Nitrogen or green matter is found in fruit and vegetable scraps, coffee grounds, and eggshells. 

Brown matter supplies the carbon and is commonly in the form of cardboard, paper, and old wood. 

Lastly, oxygen is needed so that the microorganisms can convert all ingredients into compost without the rotten smell. 

What can’t be composted?

Not all food or waste material can be included in compost. Some materials simply won’t decompose in this setting, or create unpleasant odors that can’t be controlled. Some non-compostable materials are: 

• Glass
• Metal
• Styrofoam
• Animal meat, bones, fat, and skin
• Yogurt, milk, cheese, butter
• Egg yolks and whites
• Manure from pets and meat-eating animals 
• Greasy foods and most kinds of oil
• Ashes from commercial fire logs and charcoal briquettes
• Chemically-treated wood sawdust or pieces

Paper Bags as Compostable Material

Generally, paper bags are compostable. However, to be sure, you can check a paper bag for the following characteristics to be safe:

• Made of porous paper
• Only water or soy-based ink has been printed on it
• Only starch-based adhesives have been used

Not all paper bags can be composted, however. If the adhesives, glossy finish, or staples are made with plastic or metal, they must be removed before throwing them in the compost pit. 

The following kinds of paper bags can’t be composted: 

• Metal or plastic coated bags
• Paper bags that are mixed with wax, dye or film
• Bags that have been contaminated with non-compostable waste

Even though these bags don’t qualify for composting, they can be reused as storage or regifted.

Tips for Composting Paper Bags

Shred the bag

Refrain from tossing the whole bag into the compost pit. This is unhelpful to the composting process. Shredding the paper bag breaks it down to smaller pieces that will make it easier to compost and speed up decomposition. 

Remove any stains or extra attachments

Bags that were used to store meat, oily foods or have dairy stains on them should be wiped down and dried out before composting. The same goes for tape, staplers, ribbons and any other embellishments attached to it. 

Balance the carbon-nitrogen ratio

Paper bags are a carbon source. So, try to maintain balance by adding many nitrogen-rich materials like vegetable trimmings, weeds, green leaves, coffee beans and other compost-friendly foodstuff.

Give it a good mix

Combine the bags with the rest of the compost to ensure uniformity and equal decomposition of the materials. 

How long does it take for paper bags to decompose?

The time it takes for paper bags to decompose would depend on how you dispose of them. A shredded paper bag included in a compost that is regular in size and meets all composting conditions would take six to eight weeks to break down.

However, if the compost size is too big, optimal conditions are not met and the bag is not shredded, it could take years for it to completely break down. 

Additional Tips to Make the Most of Your Paper Bags

1. Reuse them as many times as possible. You can speed up a fruit’s ripening by wrapping them in paper. 
2. Make arts and crafts projects with brown paper bags because it has rustic charm.
3. Store them for reuse at the grocery shop so you don’t need new ones.

Conclusion

By incorporating paper bags into your backyard composting efforts, you can contribute to a more sustainable future for Australia. Shredded paper bags provide valuable carbon material for your compost pile, while also diverting waste from landfills and reducing greenhouse gas emissions. 

Remember to check for any non-compostable materials on the bags and maintain a good balance of green and brown matter for optimal decomposition. Start composting today and turn your everyday waste into nutrient-rich "black gold" for your garden!