Compostable vs. Biodegradable: What’s the Difference?
Last Updated: Apr 7, 2025As you walk down the aisles at the supermarket, browsing bags of rice and cereal boxes, you may notice packages labeled as compostable, biodegradable, or recyclable. But what does it all mean?
Recyclable products mean just that: they can be recycled and should go in the recycling bin. Glass, metals, and paper, and most plastics are generally recyclable.
"Biodegradable" and "compostable" are often used interchangeably. But the fact is, these terms mean very different things. Today we're going to dive into those differences and get to the bottom of what is and isn't a smart, sustainable purchase.
Table of Contents
- What Does Compostable Mean?
- What Does Biodegradable Mean?
- What Are Oxo-Biodegradable Plastics?
- So What's a Homeowner to Do?
- Compostable and Biodegradable May Seem Similar, but They Are Oh So Different
What Does Compostable Mean?
The term "compostable" describes a product that will break down into carbon dioxide, water, inorganic compounds, and biomass in about 90 days without any toxic residue. Compostable materials will decompose into tiny pieces. They will be completely unrecognizable from the original form and with zero negative impact on the environment.
This 3-month process is the work of millions and millions of tiny microbes that eat the compostable waste and transform your trash into natural, organic compost. This resulting compost is super nutrient-rich and makes for a fantastic organic fertilizer for indoor and outdoor plants. It can also be mixed in with soil to improve overall soil quality and grow nutrient-packed fruits, vegetables, and herbs. Compost, when done correctly, does not stink and is naturally organic.
If you are composting your organics at your own home, those microbes require a little extra help to change trash into black gold.
How to Properly Care for Compost
- Water. Your compost pile or bin will need regular watering to decompose waste. Compost should be kept damp, not moist, and should be watered similarly to drought-tolerant plants.
- Oxygen. Those microbes need oxygen to break down compostable materials. Turn your compost pile once a month to assist the process. Compost tumblers make turning a cinch!
- Heat. Temperature plays a BIG part in composting. Those waste-eating microbes like their compost pile to be between 120 and 170 degrees Fahrenheit. The heat level will rise naturally with proper composting. Learn how to compost here.
What Does Biodegradable Mean?
The term "biodegradable" describes a product that will break down into carbon dioxide, water, and biomass without exposure to oxygen in a reasonable time frame. Fully biodegradable products will completely decompose in a landfill and help decrease your carbon footprint. This definition may sound the same as compostable. However, the key difference is that even though biodegradable products will break down, they will not do so in your home compost bin. Home compost rarely gets hot enough to break down biodegradable materials successfully.
What Are Oxo-Biodegradable Plastics?
Oxo-biodegradable plastics are fused with metal salts in manufacturing that accelerate the decomposition process. Oxo-biodegradable plastics have been observed to break down, but only into smaller fragments of the larger plastic product. The result is certainly less visibly polluting, but it is still pollution. These plastics can decompose further with the help of living organisms and bacteria, but that may be impossible if the plastic is underground in a landfill. Moreover, oxo-biodegradable plastics often contain cobalt, a magnetic metal that can contribute to more pollution than traditional, non-biodegradable plastic.
So What's a Homeowner to Do?
Choose Compostable Products and Packaging, When Possible
The range of biodegradable and compostable products is ever-expanding. This increase in availability is thanks to more businesses adopting environmentally-conscious practices. The compostable category is primarily focused on food containers and single-use items such as cutlery, paper plates, cups, and coffee filters.
As you browse the store shelves, you may find biodegradable straws, trash bags, and even shoes. These products are preferable to their non-biodegradable counterparts (and may not be available as compostable due to the product's composition).
You may also notice non-biodegradable and non-compostable products packaged in compostable packaging. These are certainly more desirable than their non-compostable packaged competitors. The Biodegradable Products Institute (BPI) certifies compostable products and packaging in North America, so look for that label.
For packaging, it may get simpler. This recently released story from Fast Company describes how big consumer brands partnered with Loop. These collaborations are transforming the packaged goods market by taking containers back and having the manufacturers reuse them.
Larger purchases like furniture, electronics, and home improvement materials can often be bought without packaging if you take a moment to ask. Some stores can deliver your items in reusable crates that are returned right to the store. Others may have a better recycling system for packaging materials so, it never hurts to ask!
Compostable and Biodegradable May Seem Similar, but They Are Oh So Different
It can be confusing to distinguish between compostable and biodegradable products and understand what is preferable. The key to getting it right is paying a little closer attention as you shop and choose compostable where you can.
Remember that recyclable products are not necessarily biodegradable or compostable, so read those labels before you sort your garbage. Any waste that is not properly recycled, composted, or biodegradable in a landfill may not completely decompose for 1,000 years or more!
The greatest threat to our planet is the belief that someone else will save it.
- Robert Swan, Author of Destination Antarctica.
Laura Bourland
Laura grew up in the California suburbs, far removed from environmentalism, but nature always has a way. She uprooted her life in 2015, moving to the countryside of Washington to live a more sustainable and simple life on 12 acres. She and her fiancee are learning on the job as they attempt everything from gardening and natural pest control to eco-friendly building and home improvement.