If you don’t want to place your egg cartons into the recycling bin, or you’re working on reducing waste and trash, you can compost them. Cut your paper egg cartons into smaller pieces and throw them directly into the compost bin. Egg cartons are considered a source of carbon in your carbon-nitrogen compost mix. Carbon helps to give soil its water retention capacity.
Another benefit to your garden compost is to start your seedlings in paper egg cartons. Poke holes in each cup of the egg carton for moisture to drain out. Fill each cup with potting soil and place seeds into each cup. Place in a warm spot to start germination and once the seedlings are ready to plant, place them directly in your outdoor or container gardens to grow.