How to Compost Indoors? | Three Methods That Actually Work

Indoor composting works through three methods: aerobic bins, worm bins, or bokashi fermentation, with the right choice depending on your space, odor tolerance, and how you plan to finish the compost.

Composting indoors doesn’t require a big backyard setup. The key is picking a method that fits your living space and effort level, whether you have a small apartment or under-sink storage.

The Three Main Methods for Indoor Composting

Each method handles food scraps differently. Aerobic bins use airflow and browns; worm bins rely on red wigglers; bokashi ferments scraps with bran culture. All work indoors but vary in odor, maintenance, and end product.

Aerobic Countertop or Bin Composting

This is backyard composting in a small space. You need a bin with airflow, brown materials (shredded paper, dry leaves, sawdust), and food scraps. The EPA’s home composting guidance recommends starting with a 4- to 6-inch layer of bulky browns, then layering greens and browns “like lasagna” using about 2 to 3 times the volume of browns to greens. Keep moisture like a wrung-out sponge and turn weekly. If odors appear, add more browns. If not heating up, add more greens. A viable DIY container is a plastic storage bin roughly 18×24×12 inches with 12 half-inch air holes in the bottom and top sides.

Vermicomposting (Worm Bins)

Worm bins need consistent care. Use bedding like shredded paper, cardboard, coconut coir, or dry leaves. Add about 1 pound of red wiggler worms—species matters—and feed mostly fruit and vegetable scraps. Worms can process roughly 3.5 pounds of waste per week. Keep the bin between 60°F and 80°F out of direct sunlight, with moisture like a damp sponge. Smells or flies mean overfeeding or uncovered scraps. The payoff is worm castings, a rich soil amendment.

Bokashi Fermentation

Bokashi is the most compact method, producing fermented material not finished compost. Layer food scraps with bokashi bran in a sealed bucket, press out air pockets, and let ferment for weeks. Fill to half or two-thirds full. Drain liquid every 2 to 3 days—”bokashi tea” diluted 1:100 with water can fertilize plants. Once sealed, the output must be buried in soil, mixed into a worm bin, or finished outdoors. Bokashi is best for composting meat, dairy, and cooked foods other methods can’t handle easily.

Setting Up Your Daily Scrap Collection

Regardless of method, you need a daily collection system. The EPA recommends storing fruit and vegetable scraps in a closed container on the counter, under the sink, or in the fridge or freezer. Empty it every couple of days to prevent fruit flies. Chop scraps smaller to speed decomposition, and always cover fresh waste with browns. For dedicated containers or complete systems, see our detailed roundup of the best indoor kitchen composters.

Common Mistakes and How to Fix Them

Problems come down to a few issues. Exposed scraps attract flies—cover additions with 4 to 8 inches of dry browns. Overwatering makes the pile soggy; material should be moist, not dripping. Too many greens and not enough browns causes odors—stick to about 3 parts brown to 1 part green. Not chopping scraps slows everything. For worms, wrong species or extreme temperatures crash the colony. For bokashi, failing to drain liquid creates unpleasant fermentation. The fix is almost always the same: add more carbon, reduce feeding, improve airflow.

FAQs

Can I compost if I live in an apartment with no outdoor space?

Yes. All three methods work entirely indoors. Vermicomposting and bokashi produce material you can use on houseplants, while bokashi output usually needs to be buried or finished elsewhere. Aerobic bins can produce usable compost in a small kitchen corner.

Will indoor composting smell bad?

A properly maintained system should not produce strong odors. Rotten or sour smells mean too many greens, not enough browns, or too much moisture. Fix by adding dry browns, turning, and letting the bin breathe. Avoid fruit flies by always covering scraps with browns or soil.

What should I not put in an indoor compost bin?

For most methods, avoid meat, dairy, oily foods, and large bones unless using bokashi. Also avoid diseased plants and scraps with pesticides. Stick to fruit and vegetable scraps, coffee grounds, crushed eggshells, and coffee filters for reliable results.