Compostable plastic products are popping up on store shelves more often. Are they a real solution to our plastics problem or just another example of greenwashing? Learn About Composting Day is coming up on May 29, so I decided to do some research. Read on to find out what I learned.

What is composting?

In an earlier post, I discussed the five Rs of waste reduction. Most people are aware of reduce, reuse and recycle, and many have started to refuse items to reduce waste. Composting, or “rot”, is the fifth R and one we often overlook.

Composting is a process that collects organic waste—like food and garden waste—and decomposes it over time to turn it into compost. The compost is added to soil to help plants grow.

Many people compost at home in backyard composters. Some communities, like the one where I live, have programs that collect compostable waste and transport it to a waste management facility to be turned into compost. Both are excellent options to keep organic waste out of landfills where it turns into methane and adds to our greenhouse gas emissions.

What is compostable plastic?

If you’re paying attention in the supermarket, you might have noticed the “compostable plastic” label on single-use plates, cutlery, cups, bags and plastic containers.

These are plastic items that are design to break down in a composting facility under specific temperature conditions. Many of them are also made from plant-based sources instead of fossil fuels so even their production offers some environmental benefits. (Source: World Wildlife Fund)  

Sounds great, right? Not so fast. As with many of solutions, there are limitations.

First, most bio-based plastics contain other ingredients to increase their durability. This means they don’t break down easily and can last in the environment as long as petroleum-based plastics. (Source: EPA) More importantly, composting these products isn’t as easy as it sounds.

How do you compost these plastics?

One of the challenges with these compostable plastics is they can only be composted under very specific moisture and temperature conditions. Your backyard composter doesn’t create the right conditions. This means, they need to be processed in an industrial facility.

It would be nice to think the solution is to simply toss these products in my green bin and the waste management facility will take care of them. However, most current commercial composting systems aren’t prepared to handle compostable plastics.  

So, unless you see a “home compostable” label on your products, you can’t compost them in your backyard composter, and you also can’t put them in your green waste container and send them off to a commercial facility.

(Source: Chatelaine)

Can you recycle compostable plastics?

So if composting isn’t an option, why not just put these products in your recycling bin?

Savvy recyclers are familiar with the various codes that identify which plastics are recyclable. Unlike petroleum-based plastics, compostable plastics are not recyclable. Adding them to your recyclable plastics will contaminate and disrupt the recycling stream. (Source: EPA)  

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The bottom line

Considering compostable plastic is difficult to compost and not recyclable, it’s clear that it’s not the solution many manufacturers want you to believe. It’s just another case of greenwashing where companies use eco-friendly words to make you think they’re doing the right thing.

Until better solutions are available, a better option is to reduce your dependence on single-use products and focus on stopping the waste before it starts. Make a difference by focusing your efforts on refusing, reducing and reusing. Every small change helps. Visit A year of weekly sustainable living goals for 52 ways to reduce your waste.

What are your thoughts on compostable plastic? Drop me a comment below to let me know.