Pick a bin type that fits your space and effort level
A compost bin is a container where you layer food scraps, yard waste, and other organic material so it breaks down into usable compost. You have three main routes: a sealed plastic bin you buy ready-made, a wooden or wire cage you build or assemble yourself, or an open pile on the ground with no container at all.
Sealed plastic bins cost $30 to $150, take up about 2 square feet, and work fastest because they trap heat. They are best if you have a small yard, want to keep rodents out, or live where neighbours are close. Wooden or wire bins cost $50 to $200 to build, hold more material, and let air flow freely, which speeds decomposition. Open piles cost nothing but need at least 3 feet by 3 feet of space and attract more pests. Pick sealed if you want low maintenance and fast results, wooden if you have space and don't mind turning the pile, or open only if you have room and aren't bothered by occasional wildlife.
Key Takeaways
- A sealed plastic bin is the fastest and most pest-resistant option for small spaces, while wooden bins work better if you have room and want to turn the pile yourself.
- Layer brown materials (dry leaves, cardboard, wood chips) with green materials (food scraps, grass clippings, coffee grounds) in roughly equal amounts by volume.
- 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 alone for six to twelve months.
- Never add meat, dairy, oils, or diseased plants, as these attract pests or spread plant illness.
- Finished compost looks dark brown, crumbly, and earthy, with no recognizable food scraps or leaves remaining.
Gather your materials and set up the bin
Before you add anything, decide where the bin will sit. Choose a spot that gets partial shade (full sun dries it out too fast), has decent drainage so water doesn't pool underneath, and is reasonably close to where you'll add scraps regularly. A corner of the yard or against a fence works well. If you're using a plastic bin, place it on level ground. If you're building a wooden bin, lay down cardboard or hardware cloth first to block burrowing rodents from entering from below.
Start with a 4- to 6-inch layer of brown material on the bottom — dry leaves, shredded newspaper, cardboard, or wood chips work. This creates air pockets and gives the pile structure. If you're using a plastic bin with a lid, make sure the lid closes tightly and the bin has air holes or a door near the bottom for turning and removing finished compost. Some bins come with a spigot at the base so you can drain excess liquid.
Layer brown and green materials in the right ratio
Compost needs two types of material. Brown materials are dry and carbon-rich: leaves, straw, shredded paper, cardboard, wood chips, and sawdust. Green materials are wet and nitrogen-rich: food scraps (no meat or dairy), grass clippings, coffee grounds, tea bags, and plant trimmings. Aim for roughly equal volumes of each — about one part green to one part brown, though the exact ratio is forgiving.
Add materials in layers, alternating brown and green. After you add a layer of green (like a bucket of vegetable scraps), cover it with a layer of brown (like a handful of shredded leaves). This prevents odour, keeps pests away, and balances the carbon and nitrogen the microbes need to work. If you add a lot of green material at once, add extra brown on top to cover it completely.
Keep moisture and air at the right levels
The pile should feel as moist as a wrung-out sponge — damp but not dripping. If it's too dry, decomposition slows. If it's too wet, it smells like ammonia and rots instead of composting. Check it weekly by reaching in and squeezing a handful. If water drips out, add brown material. If it feels dry, add water or green material.
Air is equally important. Microbes that break down compost need oxygen. If you're using a sealed bin, turn it every one to two weeks by rotating the drum or using the handle, which mixes the pile and brings air into the centre. If you're using an open pile or wooden bin, turn it with a pitchfork every one to two weeks. If you don't turn it, decomposition takes much longer — six to twelve months instead of two to three — but it still works. Turning speeds the process but requires more effort.
Know what to add and what to avoid
Safe to add: vegetable and fruit scraps, coffee grounds and tea bags, grass clippings, leaves, straw, shredded paper and cardboard, wood chips, plant trimmings, and crushed eggshells. These break down and feed the soil.
Never add: meat, fish, bones, dairy, oils, fats, pet waste, diseased plants, or weeds with seeds. Meat and dairy attract rats and raccoons. Oils and fats slow decomposition and smell bad. Diseased plants spread illness to your garden. Weeds with seeds will germinate when you use the finished compost. Avoid glossy or coloured paper, which may contain chemicals, and diseased leaves or branches.
Recognize when compost is ready to use
Finished compost is dark brown or black, crumbly, and smells earthy — like soil after rain. You should not see recognizable food scraps, leaves, or other original materials. If you can still identify what you added, it's not ready. The pile should have shrunk to about one-third its original size.
If you've been turning regularly, expect finished compost in two to three months. If you haven't turned it, expect six to twelve months. You don't have to wait until the entire pile is done — you can remove finished compost from the bottom of the bin and keep adding fresh material to the top. Some people keep two bins so one is finishing while they fill the other.
Troubleshoot common problems
If the pile smells like ammonia or rotten eggs, it's too wet or has too much green material. Add brown material and turn it to add air. If it smells like vinegar, it's anaerobic (lacking oxygen) — turn it more often. If it's not heating up or breaking down, it may be too dry, too cold (compost works slowly below 50°F), or have too much brown material. Add water and green material, and be patient in winter.
If you see flies or gnats, you've added meat, dairy, or oil, or you haven't covered green material with brown. Stop adding those items and bury new scraps deeper in the pile under brown material. If you see rats or raccoons, switch to a sealed bin or add a wire mesh barrier. If the pile is compacted and hard, it needs more brown material and more frequent turning to restore air pockets.
Frequently Asked Questions
Can I compost in an apartment or small space?
Yes. A sealed plastic bin takes up about 2 square feet and can sit on a balcony, patio, or in a garage. Some people use a 5-gallon bucket with a lid. The trade-off is that small bins fill quickly and need emptying more often, but they work well for one or two people producing modest amounts of scraps.
How long does it really take to get finished compost?
If you turn the pile every one to two weeks and keep moisture and temperature right, two to three months. If you turn it less often, four to six months. If you don't turn it at all, six to twelve months. Cold weather slows everything down, so winter batches take longer than summer ones.
What if I don't have a yard?
A sealed plastic bin on a balcony or patio works. You can also use a small wooden bin, a 5-gallon bucket, or even a large opaque storage container with holes drilled in the sides. Some apartments allow small bins in shared courtyards. Check your lease first.
Do I need to add anything to speed up decomposition?
No. Compost breaks down on its own as long as you have the right mix of brown and green, moisture, and air. Commercial compost starters and accelerators are not necessary. Finished compost or garden soil already contains the microbes you need.
Can I use finished compost right away or does it need to cure?
You can use it right away in most cases. If it still feels hot or smells strongly of ammonia, let it sit for a few weeks. Otherwise, mix it into garden beds or use it as mulch around plants. It won't burn plants the way fresh manure can.