Start composting kitchen scraps in a bin or pile

You can compost most of your kitchen waste—fruit and vegetable scraps, coffee grounds, eggshells, and plant trimmings—by layering them with dry materials like leaves or shredded paper in a bin or outdoor pile. The microorganisms and insects that live in the pile break down these materials into dark, crumbly compost you can use in gardens or potted plants. The process takes anywhere from two months to a year depending on how often you turn the pile, the size of your pieces, and the season.

You do not need special equipment or a large yard. A straightforward wire bin, wooden box, or even a corner of your garden works. Indoor composters and countertop bins are also available if you have limited space, though they require more frequent maintenance and sometimes cost money upfront.

Key Takeaways

  • Layer wet kitchen scraps (fruit, vegetable peels, coffee grounds) with dry materials (leaves, shredded paper, cardboard) in a ratio of roughly one part wet to two parts dry.
  • Keep the pile as moist as a wrung-out sponge and turn it every one to two weeks if you want finished compost in two to three months, or leave it undisturbed for six months to a year.
  • Avoid composting meat, dairy, oils, pet waste, and diseased plants, as these attract pests or introduce harmful pathogens.
  • Finished compost is dark brown, crumbly, and smells earthy; use it to enrich garden soil or mix it into potting soil for containers.

What kitchen scraps you can and cannot compost

Safe to compost: fruit and vegetable scraps (peels, cores, stems, wilted leaves), coffee grounds and tea bags, crushed eggshells, plant trimmings, grass clippings, and shredded paper or cardboard. Citrus peels, onion skins, and garlic take longer to break down but will eventually decompose. Cooked vegetables without oil or salt are also fine, though raw scraps decompose faster.

Do not compost: meat, fish, bones, dairy products, oils, fats, and grease—these attract rats, raccoons, and flies. Avoid diseased plants, pet waste, and glossy or colored paper. Bread and grains can work but often attract pests in outdoor piles. If you use a sealed indoor composter, follow its instructions, as some models can handle a wider range of materials.

Setting up a compost bin or pile

Choose a location that gets partial shade and drains well—a corner of your yard, against a fence, or under a tree works. If you are using a bin, place it directly on soil so worms and microorganisms can enter from below. If you are building a pile, start with a layer of coarse material like twigs or straw about four inches deep to allow air to flow underneath.

For a bin, you can buy a plastic tumbler (which speeds decomposition but costs $50 to $150), a wire or wooden frame (cheaper and simpler), or make one from a plastic storage container with holes drilled in the sides and bottom. For a pile, you need nothing but space—just start layering. Either way, keep the pile at least three feet wide and three feet tall so it heats up enough to decompose quickly.

Layering wet and dry materials correctly

Alternate layers of wet kitchen scraps with dry materials to keep the pile balanced. Wet materials (fruit, vegetable scraps, grass clippings, coffee grounds) are high in nitrogen. Dry materials (leaves, shredded paper, cardboard, straw) are high in carbon. A rough ratio is one part wet to two parts dry by volume, though exact measurements are not critical—if your pile smells like ammonia, add more dry material; if it is not breaking down, add more wet material.

Chop or tear larger pieces into smaller chunks—roughly the size of your thumb—so they decompose faster. Whole apple cores or large vegetable scraps can take months to break down. Shred paper and cardboard into strips rather than leaving them in sheets. Each time you add kitchen scraps, cover them with a layer of dry material to reduce odors and discourage pests.

Moisture, temperature, and turning the pile

Keep the pile as moist as a wrung-out sponge. Squeeze a handful of compost; a few drops of water should come out. If it is dry, water it. If it is soggy and smells like rotten eggs, turn it and add dry material. In dry weather, water the pile every week or two. In rainy weather, you may need to cover it with a tarp or move it under a roof.

Turning the pile every one to two weeks speeds decomposition by introducing oxygen, which the microorganisms need. Use a pitchfork or shovel to move material from the outside of the pile to the center. If you turn it regularly, you can have finished compost in two to three months. If you leave it undisturbed, it will take six months to a year. Temperature also matters: piles decompose faster in warm months and slow down in winter, though they do not stop entirely.

Recognizing finished compost and using it

Finished compost is dark brown or black, crumbly, and smells earthy—like soil after rain. You should not be able to identify the original scraps. If you still see chunks of vegetable or paper, the pile needs more time. Sift finished compost through a quarter-inch screen or your hands to remove any remaining twigs or unbroken pieces, then use it right away or store it in a bin.

Mix finished compost into garden beds at a depth of two to four inches before planting. For potted plants, blend one part finished compost with two parts potting soil. You can also use it as a mulch around the base of trees and shrubs. A mature pile produces roughly one-third the volume of the original materials—a three-foot pile might yield enough compost to fill a five-gallon bucket or two.

Troubleshooting common problems

Pile smells bad (rotten eggs or ammonia): This means the pile is too wet or too dense. Turn it, add dry material like shredded paper or leaves, and reduce watering. Bad smells usually go away within a few days of turning.

Pile is not heating up or breaking down: The pile may be too small, too dry, or lacking nitrogen. Make sure it is at least three feet on each side, water it, and add more wet materials like grass clippings or vegetable scraps. Turning it also helps.

Pests (rats, raccoons, flies): You are composting meat, dairy, or oils—stop when ready. Cover kitchen scraps with a thick layer of dry material. If you have a bin, make sure the lid closes tightly and the bottom is sealed or sits on hardware cloth. Bury food scraps deeper in the pile rather than leaving them on top.

Pile is soggy after rain: Cover it with a tarp or move it to a spot with better drainage. Add dry material and turn it to introduce air.

Frequently Asked Questions

Can I compost cooked food?

Cooked vegetables without oil, butter, or salt are fine and will break down. Avoid cooked meat, fish, dairy, and anything with oil or grease, as these attract pests. Cooked food also decomposes more slowly than raw scraps.

How do I compost if I live in an apartment?

Use a countertop composter, a sealed bokashi bucket (which ferments scraps and requires a small outdoor space to bury the result), or store scraps in a freezer bag and take them to a community garden or farmers market that accepts compost. Some cities also run drop-off compost programs.

Do I need to add worms to my pile?

No. Outdoor piles decompose through bacteria and fungi; worms arrive naturally from the soil. Worms are helpful but not required. If you want to speed things up, you can buy red wigglers and add them to a bin, but this is optional.

What if my compost pile attracts ants?

Ants usually mean the pile is too dry. Water it and turn it. Ants themselves do not harm the compost, but if they bother you, keeping the pile moist discourages them.

Can I compost sawdust or wood chips?

Yes, but use only untreated wood. Sawdust from pressure-treated lumber or painted wood contains chemicals and should not go in compost. Untreated sawdust and wood chips break down slowly, so shred or chop them into small pieces and mix them with wet materials.