What can you compost? & What you Can't

All compost ingredients that are suitable for use are organic, meaning they come from living or previously living sources such as plants, animals, and their natural by-products.

In nature, animals and plants have a life cycle, when they die, they break down and decay, providing food for fungi and bacteria. These microorganisms then become food for other creatures, such as bugs, which in turn are eaten by frogs, and so on up the food chain.

This natural decomposition process also enriches the soil with nutrients and materials that support plant growth. Composting helps to facilitate this transformation of organic matter into food for soil creatures and plants.

However, inorganic materials do not break down in this manner and should be avoided in the compost bin.

You can’t compost inorganic materials such as:

Plastic – can take up to 500yrs to decompose
Styrofoam
Aluminum
Glass
Rocks

You can compost these organic materials:

Grass clippings
Shredded paper
Vegetables
Fruit
Leaves
Horse or cow manure
Coffee grounds and filters
Newspaper
Tea leaves and bags
Eggshells, crushed
Hay or straw
Garden wastes, flowers, yard trimmings excluding invasive weeds such as knotweed
Pine needles and cones
Shredded cardboard
Sawdust
Nut shells, acorns
Seaweed
Peanut hulls
Spent beer or wine
Flat soda or sports drinks

Some organic materials shouldn’t be composted in your ordinary home compost heap (such as compost bins and tumblers) due to health, odor, and safety concerns. You would also need to make sure that your pile reaches between 130°F to 160°F in the center.
These items include to name few:

Human Waste
Meat
Fish
Raw Egg
Dog Waste
Cat Waste
Road kill or other dead animal
Organic poisons like boric acid
Oil
Grease
Dairy
Diseased plants
Weeds that have gone to seed (actually, it’s the weed seeds you should avoid, the rest of the plant is OK)

These materials will still decompose, but the small size of a home composting system cannot effectively address the issues that may arise during the decomposition process.

Check Your Needs First

It’s important to consider your specific needs and safety when it comes to home composting. While earlier in this article, pine needles and cones were mentioned as acceptable materials for composting, it’s crucial to avoid using them if you have a pine allergy, if children who will be playing on the fertilized lawn have a pine allergy, or if the pine tree has been sprayed with pesticides. Always take into account your household’s unique requirements before choosing materials for composting.