Making a backyard compost bin doesn’t require a store-bought unit. A simple open pile or a DIY bin in a dry, shady spot works just as well. The best location is easily accessible year-round, has good drainage, sits near a water source, and isn’t pressed against a fence. Before you build, decide where the bin will live — that choice matters more than the materials.
Where To Put A Compost Bin
Choose a dry, partly shady spot with good drainage and a nearby water source. The EPA’s home composting guidance emphasizes year-round access and a spot where water doesn’t pool or collect.
Keep the bin a few inches away from fences and walls. Packing it tight blocks airflow behind the bin and makes turning awkward. You’ll also want enough room to stand beside it with a pitchfork.
What Size Should The Bin Be?
An ideal compost area is about 3 feet wide by 3 feet deep by 3 feet tall — roughly one cubic yard. That size holds enough heat to break down material efficiently while staying small enough to turn by hand.
Smaller piles work but break down slower. Larger piles get hard to turn and may go anaerobic in the middle, which is the main cause of bad smells.
Five DIY Compost Bin Options
These buildable systems come from university extension services and require basic tools. All of them work; choose based on what materials you have on hand.
- Wood 3-bin system: University of Wisconsin Extension provides do-it-yourself plans for a “Wood 3-Bin Composter.” Three bays let you rotate material as it matures.
- Concrete-block system:
- Barrel system: Roll the barrel to turn the compost.
- Trash-can system:
- Pallet system: UF/IFAS Extension’s “Building A Compost Bin With Shipping Pallets” uses pallets, L brackets, hinges, and a latch.
Whichever you build, chop or shred larger pieces before adding them. That single step speeds up the entire process. If you’re weighing whether a store-bought unit is worth it, our tested roundup of the best backyard compost bins covers the options that hold up over years of use.
What Goes In And How To Maintain It
Browns include dry leaves, twigs, straw, cardboard, and shredded newspaper. Greens include fruit and vegetable scraps, grass clippings, coffee grounds, and plant scraps.
| Material | Examples | Role |
|---|---|---|
| Browns (carbon) | Dry leaves, straw, cardboard, shredded paper | Provide structure and energy for microbes |
| Greens (nitrogen) | Fruit scraps, grass clippings, coffee grounds | Feed microbes and generate heat |
| Air | Turning, fluffing, block gaps | Prevents odor and speeds breakdown |
| Moisture | Water source nearby | Keeps material like a wrung-out sponge |
Keep the pile as moist as a wrung-out sponge. If it’s too dry, water it while turning. If it’s too wet, add more browns. Don’t rely on wood chips or sawdust alone as the brown balance in a trash-can system — University of Wisconsin Extension notes the carbon in woody material isn’t readily available to microbes, so include leaves or paper as part of the browns.
Turn or fluff the pile regularly. Lack of air is the most common cause of odor. A tarp over the top is optional but helps retain moisture.
Compost is ready when it’s dark, rich in color, and smells like rich soil. Depending on conditions, that can take anywhere from two months to two years, per the EPA’s home composting guidance. Odor usually means too much moisture, too many greens, or not enough turning — fix those three and the smell follows.
FAQs
Can I compost in winter?
Yes, though the pile slows down. Microbial activity drops in cold temperatures, but the process continues. Keep adding materials through winter and turn less often. The center of a large pile can stay warm enough to keep working; a smaller pile may freeze solid until spring thaw.
How do I keep animals out of the bin?
A secure lid or a tarp weighted down at the edges also discourages raccoons and rodents. If animals persist, switch to an enclosed barrel or bin design.
Why does my compost smell like rotten eggs?
That smell means the pile is too wet or too compacted, which starves it of oxygen. Turn the pile thoroughly, add dry browns like leaves or shredded cardboard, and make sure drainage holes aren’t blocked. The smell usually clears within a few days once airflow is restored.
References & Sources
- EPA. “Composting At Home.” Provides siting guidance, material ratios, and decomposition timelines.
- University of Wisconsin Extension. “Wood 3-Bin Composter — Do-It-Yourself Compost Bin Instructions.” Source for the wood, concrete-block, barrel, and trash-can bin designs.