Start composting with scraps you already throw away
You can turn kitchen waste into compost in a container as small as a plastic bin under your sink or as large as a pile in your yard. The basic process is the same: layer food scraps with dry material like leaves or shredded paper, keep it moist, turn it occasionally, and wait. Most home systems produce usable compost in two to six months, depending on how often you turn the pile and what you put in it.
The speed and smell depend on what you add and how you manage it. A hot pile that you turn weekly will break down faster and smell less than a passive pile you leave alone. Either way works — the difference is time and effort, not results.
Key Takeaways
- Layer food scraps with dry material like leaves, shredded paper, or cardboard to balance moisture and air, which speeds decomposition and reduces odor.
- Avoid meat, dairy, oils, and pet waste, which attract pests or introduce pathogens that home compost does not get hot enough to kill.
- Keep the pile as moist as a wrung-out sponge and turn it weekly if you want compost in two to three months, or leave it alone for four to six months.
- You can compost in a bin, a pile, a tumbler, or even a sealed container indoors, depending on your space and how much waste you generate.
What kitchen waste breaks down and what does not
Safe to compost: vegetable and fruit scraps, coffee grounds and tea bags, eggshells, bread, pasta, rice, and plant-based food waste. These materials break down quickly and feed the microbes that do the work.
Do not compost: meat, fish, bones, dairy, oils, fats, and pet waste. Meat and dairy attract rats and raccoons. Oils slow decomposition. Pet waste can carry parasites that home compost does not heat up enough to kill. Diseased plants and weeds with seeds can survive the process and spread problems to your garden.
Cooked food is safe as long as it contains no meat, dairy, or oil. Citrus peels, onion skins, and garlic take longer to break down but will decompose eventually. If you have a lot of one type of scrap — say, a bushel of apple cores — spread them out over weeks rather than adding them all at once, which can create a wet, smelly layer.
The two-material system: greens and browns
Compost needs both nitrogen-rich material (greens) and carbon-rich material (browns). Greens are your food scraps, grass clippings, and plant trimmings. Browns are dry leaves, shredded paper, cardboard, straw, and wood chips. The ratio matters: aim for roughly three parts brown to one part green by volume. Too much green and the pile gets wet, compacted, and smelly. Too much brown and decomposition slows to a crawl.
If you live in an apartment or have no yard, you can still compost. Save your food scraps in a sealed container in the freezer, then add them to a community garden's compost pile, a local farm, or a municipal drop-off site. Some cities run collection programs where you put scraps in a bin and they haul it away to a commercial facility.
If you have outdoor space, collect leaves in fall and store them in a bag or bin. Shred them by running a lawn mower over them — shredded material decomposes faster than whole leaves. Keep a pile of this material next to your compost bin so you can layer it in as you add scraps.
Building and maintaining a basic pile or bin
Start with a container or a designated spot on the ground. A wooden pallet frame, a wire cylinder, a plastic bin with holes drilled in the sides, or even a corner of your yard all work. The container just needs to let air in and let water drain out.
Layer your materials: a few inches of brown, then a few inches of green, then brown again. Water each layer as you go so the whole pile is moist but not soggy — like a wrung-out sponge. If it smells like ammonia or rotten eggs, it is too wet; add more brown material and turn it. If it is not heating up and breaking down, it is probably too dry; add water or more green material.
Turn the pile every week or two if you want compost in two to three months. Use a pitchfork to move material from the outside edges into the center, where it is hottest. If you do not turn it, the pile will still decompose, just more slowly — four to six months or longer. Turning speeds things up because it introduces oxygen, which the decomposing microbes need.
Tumblers and enclosed bins for faster results
A compost tumbler is a barrel mounted on a frame that you rotate by hand. You add scraps through a door, seal it, and turn the barrel every few days. Tumblers heat up faster than open piles because they trap heat and moisture, so they produce finished compost in six to eight weeks. They also keep out pests and smell less because everything is enclosed.
Tumblers cost between $100 and $400 depending on size and material. A wooden or plastic bin with a lid costs less — $30 to $100 — but takes longer and requires more hands-on turning. An open pile costs nothing but takes the most time and space.
For apartment dwellers, bokashi bins are a sealed option that ferments food scraps (including meat and dairy) in two weeks using special bran. The fermented material then goes into a regular compost pile or buried in soil to finish breaking down. Bokashi bins are small, odor-controlled, and work indoors, but they require buying the special bran regularly.
Knowing when compost is ready to use
Finished compost looks like dark brown soil, crumbles in your hand, and smells earthy. You should not be able to identify the original scraps — if you can see apple peels or carrot chunks, it is not done yet. The pile should have shrunk to about one-third its original volume.
If you are turning regularly, you can harvest from the bottom of the pile while the top is still decomposing. Use a pitchfork to pull finished material out from underneath. If you are not turning, wait until the whole pile looks uniform and dark before harvesting.
Use finished compost to amend garden beds, pot soil, or lawn. Mix it into the top few inches of soil or use it as mulch around plants. There is no such thing as too much compost — it improves soil structure, water retention, and nutrient content no matter how much you add.
Troubleshooting common problems
Smell: If the pile smells bad, it is too wet or has too much green material. Add brown material and turn it to introduce air. A working compost pile should smell earthy, not rotten.
Pests: Rats, raccoons, and flies are attracted to meat, dairy, and oils. Do not add these. If you already have pests, bury food scraps deeper in the pile and cover the top with a layer of brown material. A tumbler or enclosed bin prevents most pest problems.
Slow decomposition: The pile is too dry or too brown. Add water and more green material (food scraps or grass clippings). Shred brown material into smaller pieces so it breaks down faster. Cold weather also slows decomposition — piles work slower in winter but do not stop.
Wet, compacted pile: Too much green material or not enough air. Add brown material, break up compacted sections with a pitchfork, and turn more often. Drilling holes in the sides of a bin helps air flow.
Frequently Asked Questions
Can I compost in winter?
Yes, but decomposition slows significantly in cold weather. A pile that would finish in three months in summer might take six months in winter. Insulating the pile with straw or leaves helps retain heat. An enclosed tumbler or bin stays warmer than an open pile.
What do I do if my compost pile smells like ammonia?
That smell means too much nitrogen (green material) and not enough oxygen. Add brown material like shredded paper or leaves, and turn the pile thoroughly. The smell should fade within a few days as air mixes in.
Can I compost paper and cardboard?
Yes. Shred or tear paper and cardboard into small pieces so they break down faster. Avoid glossy paper, colored inks, and cardboard with plastic coating. Plain newspaper, brown paper bags, and plain cardboard boxes all work well.
How much space do I need to compost?
A pile needs at least three feet by three feet to heat up properly, but you can compost in a smaller bin or tumbler. An apartment dweller can use a bokashi bin or save scraps for a community compost site.
Do I need to add anything to speed up composting?
No. Compost happens naturally as long as you balance greens and browns, keep it moist, and turn it occasionally. Commercial compost starters and accelerators are not necessary — the microbes are already in your materials.