A start-to-finish backyard composting guide — where to put the pile, how to layer it, what to feed it, what to keep out, and how to fix it when something goes sideways.
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Good siting solves half your problems before you start.
Avoid low areas where water pools. Standing water suffocates the pile and turns it anaerobic (smelly).
Full sun dries the pile out; deep shade keeps it cold. Dappled shade or morning sun is the sweet spot.
You'll wet the pile as you build it and again when you turn it. A hose within reach makes this easy.
If it's a hike, you'll stop feeding it. Keep it close, but at least a few feet from wooden structures.
Direct soil contact lets worms and microbes move in from below and drains excess moisture.
A pile roughly 3×3×3 ft (1 cubic yard) holds heat well. Smaller piles work but decompose more slowly and rarely get hot.
Start with 4–6 inches of coarse, woody material directly on the soil: small twigs, chopped corn stalks, straw, or wood chips. This creates airflow underneath so the pile can breathe from the bottom up.
Add 2–3 inches of nitrogen-rich greens: fresh grass clippings, kitchen scraps, coffee grounds, plant trimmings, or manure from chickens/rabbits/horses. Chop or crush anything bigger than a fist so it breaks down evenly.
Cover the greens with another 4–6 inches of dry browns: shredded leaves, straw, cardboard, shredded newspaper, or sawdust. Browns should always be the top layer — this locks in odor and keeps flies away.
Optionally sprinkle a shovel of finished compost or garden soil on top to inoculate the pile with microbes. Then water each layer until it feels like a wrung-out sponge — damp, not soggy.
Every time you add greens (kitchen scraps, grass), cover with 2–3× that volume in browns. Aim for roughly 3 parts brown to 1 part green by volume. Keep browns stockpiled nearby so this is easy.
Use a pitchfork or compost aerator to move outside material to the center. Turning adds oxygen, evens moisture, and is what makes a pile heat up. A pile you never turn still works — just slower.
Finished compost is dark, crumbly, smells like forest floor, and you can no longer recognize the ingredients. In a hot, well-managed pile this takes 2–4 months; a passive pile takes 6–12 months. Sift out any large chunks and toss them back to keep composting.
Roughly 3:1 by volume (browns : greens). By weight this is closer to a 25–30:1 carbon-to-nitrogen ratio.
Dry, brown, high-carbon. These feed structure and airflow.
Wet, fresh, high-nitrogen. These fuel the microbes and heat.
Add what you're putting in and how much. We'll blend the carbon-to-nitrogen ratio and tell you if it's balanced.
Too brown (high C:N). Add about 6.3 parts Fresh grass clippings to hit ~30:1.
Smaller pieces have more surface area. A shovel-chop of kitchen scraps or a pass with the mower over leaves can double your decomposition speed.
Stash a trash can of dry leaves or shredded cardboard next to the pile so you can always cover fresh greens without a trip across the yard.
New scraps go in the hot middle, not the top. Fewer flies, faster breakdown, less smell.
Grab a handful and squeeze. A drop or two of water = perfect. Streams = too wet, add browns. Nothing = too dry, water it.
Fill bin A while bin B finishes. When A is full, stop adding and start on B — A will be ready by the time B is full.
A tarp keeps the pile from drowning. In dry climates, a tarp also traps moisture and heat.
A shovel of either inoculates the pile with the microbes it needs. Bagged 'compost starter' isn't required.
3:1 browns to greens is a target, not a rule. If it smells or slumps, add browns. If it's cold and dry, add greens and water.
Leaving these out prevents most odor, pest, and contamination problems.
Fine in small amounts, but too much throws the pile off.
You manage the pile (size, ratio, moisture, turning). It heats to 130–150°F, kills many weed seeds and pathogens, and can finish in 2–4 months.
You add materials and mostly leave it alone. It still works, but takes 6–12+ months and may not kill weed seeds or diseases.
Simplest, cheapest.
Best all-around backyard option.
Tidy and convenient, smaller capacity.
Best if you compost a lot.
Neat but needs good turning.
Great for kitchen scraps in small spaces.
Start new piles, use finished compost on beds.
Watch moisture closely, cover during heavy rain.
Best time to build big piles — leaves are abundant.
Pile slows down; keep adding scraps and cover with browns.
Match the symptom, then work the fixes in order.
Likely cause: Pile is anaerobic — too wet, too compact, or too many greens with no air.
Likely cause: Way too much nitrogen — usually too many fresh grass clippings, manure, or kitchen scraps with no browns to balance them.
Likely cause: Usually too dry, too small, too many browns, or pieces too big.
Likely cause: Not enough nitrogen, not enough mass, too dry, or too cold outside.
Likely cause: Too much nitrogen and too little airflow — the pile is 'cooking' and killing off the beneficial microbes doing the work.
Likely cause: Meat, dairy, oily food, or exposed kitchen scraps on top of the pile.
Likely cause: Uncovered in heavy rain, or built almost entirely from wet greens.
Likely cause: Too much sun exposure, too many browns, no watering.