What you need to begin composting in a bin

A compost bin is a container that holds kitchen scraps and yard waste while they break down into usable compost. You can start one with a plastic storage bin, a wooden box, or a purpose-built compost container—the bin itself is less important than what goes inside it and how you manage it. The basic setup takes an afternoon and costs between $20 and $150 depending on whether you build or buy the bin.

Before you choose a bin, decide where it will live. Compost works best in a spot that gets partial sun (at least a few hours a day), stays reasonably accessible so you can add to it regularly, and drains well. A corner of a yard, a patio, or even a balcony works. Avoid placing it directly against a house wall or in deep shade, where it will decompose slowly and may attract pests.

Key Takeaways

  • A working compost bin needs a mix of "brown" materials (dry leaves, shredded paper, cardboard) and "green" materials (food scraps, grass clippings) in roughly equal amounts by volume.
  • Start your bin by layering browns and greens, then add water until the pile feels like a wrung-out sponge—wet enough to break down but not waterlogged.
  • Drill or poke holes in the bottom and sides of your bin so air can reach the pile; without oxygen, compost becomes a smelly anaerobic mess.
  • Turn or mix the pile every one to two weeks to speed decomposition; finished compost is dark, crumbly, and ready to use in three to six months.
  • Never add meat, dairy, oils, or pet waste to your bin, as these attract pests or introduce harmful pathogens.

Choosing and preparing your bin

If you are building your own bin, a wooden box made from untreated lumber works well and costs $30 to $60 in materials. A 3-by-3-foot footprint gives you enough volume to maintain proper temperature and moisture without being unwieldy. Avoid pressure-treated wood, which contains chemicals that leach into compost.

If you are buying a bin, look for one with a hinged or removable lid and a door or opening near the bottom so you can harvest finished compost without dismantling the whole thing. Plastic bins marketed as compost tumblers or stationary bins both work; tumblers speed up the process but cost more and take up less space, while stationary bins are cheaper and simpler.

Once you have your bin in place, drill or poke holes in the bottom and all four sides. Use a 1/4-inch drill bit or a nail to make holes about 6 inches apart. These holes let air flow through the pile, which is essential—compost needs oxygen to break down properly. Without airflow, your pile will become anaerobic (oxygen-starved) and smell like rotten eggs or ammonia.

Layering your first batch of materials

Start your bin by alternating layers of brown and green materials, beginning with a 4-inch layer of brown. Browns are dry, carbon-rich materials: shredded leaves, shredded newspaper or cardboard, straw, or wood chips. Greens are nitrogen-rich and moist: grass clippings, vegetable scraps, coffee grounds, and plant trimmings. Aim for roughly equal volumes of each, though the exact ratio is forgiving—anywhere from 1:1 to 3:1 brown-to-green works.

Layer them like a lasagna: 4 inches of brown, then 4 inches of green, then brown again, until your bin is full or you run out of material. If you are starting in fall, you will have plenty of leaves; in spring or summer, you may need to save kitchen scraps for a few weeks before you have enough green material to begin. You can start with whatever you have on hand and add more as it becomes available.

After each layer, sprinkle water lightly so the pile feels like a wrung-out sponge—moist but not soggy. If water pools at the bottom, you have added too much; if the pile feels dry, add more. The moisture helps microbes break down the materials, but too much water blocks oxygen and creates odor problems.

Maintaining moisture and temperature

Check your pile once a week by reaching into it and squeezing a handful. If it feels dry, add water with a hose or watering can. If it feels waterlogged, add brown materials (dry leaves or shredded paper) to absorb excess moisture. The pile should always feel like a damp sponge, not a wet mop.

As microbes break down the materials, the pile generates heat—a working compost pile can reach 130 to 150 degrees Fahrenheit in the center. This heat is normal and actually speeds decomposition. If your pile never warms up, it usually means either not enough green material (which provides nitrogen for the microbes to feed on) or not enough moisture. Add more greens or water and wait a few days.

In winter, compost slows dramatically or stops in cold climates because microbial activity drops. You can keep adding materials to your bin, but decomposition will resume when temperatures rise in spring. If you live in a freezing climate and want year-round composting, insulate your bin with straw bales or leaves around the outside.

Turning the pile to speed decomposition

Every one to two weeks, mix or turn your pile by moving material from the outside edges toward the center. This brings fresh oxygen to the microbes and redistributes moisture evenly. You can use a garden fork, a shovel, or even a stick—just stir it enough that the pile looks mixed rather than layered.

If you have a tumbler-style bin, straightforward rotate it according to the manufacturer's instructions, usually every few days. Turning takes 10 to 15 minutes and is the single most effective way to speed up composting. A regularly turned pile can produce finished compost in 6 to 8 weeks; an unturned pile takes 3 to 6 months or longer.

You will know it is time to turn when the pile has settled noticeably or when the outer edges look darker and more broken down than the center. If you forget to turn for a few weeks, do not worry—the pile will still decompose, just more slowly.

What to add and what to avoid

Safe to add: vegetable and fruit scraps, coffee grounds and tea bags, grass clippings, plant trimmings, leaves, shredded newspaper and cardboard, straw, wood chips, and crushed eggshells. These materials break down reliably and do not attract pests or introduce problems.

Never add: meat, fish, bones, dairy products, oils or fats, pet waste, diseased plants, or weeds with seeds. Meat and dairy attract rats and other pests. Oils slow decomposition. Pet waste and diseased plants introduce pathogens that survive the composting process. Weeds with mature seeds may survive and sprout in your finished compost.

Citrus peels, onions, and garlic can go in your bin but use them sparingly—large amounts can slow decomposition and repel worms if you later use the compost in a worm bin. Glossy or colored paper should not be added; stick to plain newspaper and plain cardboard.

Harvesting finished compost

Finished compost is dark brown or black, crumbly, and smells earthy—not like rotting food. It should hold together loosely when you squeeze it but fall apart easily. If you see recognizable food scraps or leaves, it is not ready yet; let it sit for another few weeks.

To harvest, stop adding new material to the bin and let the pile sit for one to two weeks. Then remove the finished compost from the bottom using the door or opening on your bin. Sift out any large pieces that have not fully broken down and return them to the bin to continue composting.

Use your finished compost to amend garden beds, mix into potting soil, or top-dress lawns. A bin that is actively maintained can produce 1 to 2 cubic feet of finished compost every 2 to 3 months, depending on the size of your bin and how often you turn it.

Frequently Asked Questions

Can I use a regular plastic storage bin from a hardware store?

Yes. Drill holes in the bottom and sides, add a layer of brown material on the bottom so scraps do not sit in water, and proceed as normal. Storage bins work best for smaller-scale composting and may need more frequent turning because they have less volume to generate heat.

Why does my compost smell bad?

A rotten-egg or ammonia smell means the pile is anaerobic (not enough oxygen). Turn it when ready and drill more holes in the bin if needed. A sour or vinegary smell usually means too much moisture; add brown materials and turn the pile. A working compost pile should smell earthy or neutral, not foul.

How do I know if my bin is too wet or too dry?

Squeeze a handful of material from the center of the pile. If water drips out, it is too wet—add shredded leaves or cardboard. If it crumbles and does not hold together at all, it is too dry—add water or green materials. The goal is a consistency like a wrung-out sponge.

Do I need to add compost starter or microbes?

No. Microbes are already present in soil, leaves, and food scraps. A handful of finished compost or garden soil mixed into your new pile can speed things up slightly, but it is not necessary. Your pile will compost on its own.

Can I compost in winter?

Yes, but decomposition slows dramatically in freezing temperatures. You can keep adding materials, and the pile will resume breaking them down when it warms up. Insulating the bin with straw or leaves helps maintain some heat in mild winters.