Wondering if those green, bioplastic compostable bin liners are bad for your compost? Read on for more details about whether you can safely use a green compostable bin liner for your compost bucket.
Last week, a friend reached out to ask about compostable bin liners for the countertop bin she uses to collect food scraps for composting. She does not process the compost herself (like in a backyard bin or tumbler). She is one of the lucky ones and has municipal composting in her community; her town offers organic waste pickup, including food waste.
If you’re not familiar with this service, it’s the same as having your trash or recycling collected. She has a separate green bin for food scraps and yard waste and sets it out for collection on a predetermined schedule.
Are compostable green bags bad for your compost bin?
She specifically called to ask about green compostable liner bags, thin bags that line countertop bins to make the composting process easier and less “gross”. You use them in the same way you use trash bags to collect your landfill waste in a kitchen trash bin, but they are much smaller and not made from fossil fuels/petrochemicals (i.e. plastic)
These compostable bags are made from a variety of plant-based bioplastics (corn, potato, etc…). When placed in the right composting systems, they break down much like food waste and do not contaminate a compost pile.
Check for compostable certifications
As an aside, if you choose to use these, check to confirm they are certified to be compostable before you buy them. BPI Compostable and OK Compost are the two most common certifications. I did a much deeper dive into these certifications, what they mean, and how to find them in this post, so check that out for more details.
Industrial vs home compostable
In that deeper dive, I discuss the difference between something that can be composted at home and something that ought to be composted in an industrial facility. This distinction gets at the heart of my friend’s question.
Industrial compost facilities are generally managed with more precision and heat. Bioplastics, like the material from which these green compostable liner bags are made, break down just fine in industrial facilities but can take a very long time to decompose in home bins.
Compostable bin liners don’t contaminate compost piles
For someone looking to manage a home compost bin elegantly and quickly, these green bags might feel annoying and out of place. They’ll probably need to be sifted out of otherwise finished compost and added to another pile to continue breaking down once or twice before they disappear into the abyss of organic matter.
They will not, however, contaminate your home compost bin. And they won’t cause an issue in an industrial facility (where your municipal green bin pick-up service is almost certainly taking your organic waste).
Are compost bin liners necessary?
They’re nice to have but not necessary. I answered this question more fully in a separate post, so take a read if you’re curious.
Are there other options for compostable bin liners?
Green bin liners are the most common liners for countertop compost bins, but you can use anything compostable. Brown paper bags are my favorite compost bin liners because they are more durable than the green bioplastic bags and they provide compost browns to help keep the bucket or bin a bit more balanced.
Using bin liners is better than tossing food waste in the trash
In the end, bin liners are not necessary but nice to have (for most people). They add one more cost to the process and one more thing to produce, transport, and toss to get our food scraps processed into soil amendment instead of languishing in landfills. That’s not perfect.
But if compostable bin liners help lots of people overcome the hurdle of separating their food scraps and making the habit more tolerable, then it’s well worth using them.
P.S. If you find the compostable bags break from time to time, try adding some dry “brown” materials like paper scraps or cardboard to the bin. These will help keep the bin a little bit drier, which makes it cleaner and reduces the amount of moisture in the bin that causes the green bioplastic bag to break down more quickly.
Got any other questions? Leave them below. I’ll do my best to answer them.
Complete Guide To Composting At Home
For more information about how to compost at home, check out our Complete Guide To Compost At Home with loads of articles to answer all your questions about how to compost at home. We have resources, FAQs, interviews with everyday families who compost at home, and more!
Jen Panaro, founder and editor-in-chief of Honestly Modern, is a self-proclaimed composting nerd and an advocate for sustainable living for modern families. In her spare time, she’s a serial library book borrower, a messy gardener, and a mom of two boys who spends a lot of time in hockey rinks and on baseball fields.
You can find more of her work at Raising Global Kidizens, an online space to help parents and caregivers raise the next generation of responsible global citizens.