How to Start a Compost Pile
Pick a level, part-shaded spot on bare soil, lay 4-6 inches of coarse browns, then add roughly 2-3 parts browns to 1 part greens until the pile is about 3 ft (1 m) tall. Water it until it feels like a wrung-out sponge and turn it every week or two.
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Before you start: what you need
You need three things: a spot, a supply of browns, and a supply of greens. A garden fork and a hose or watering can make the job easier. You do not need a bin, an activator or any special kit.
- Browns (carbon-rich, usually dry): fall leaves, straw, shredded cardboard, newspaper, small twigs, wood chips
- Greens (nitrogen-rich, usually moist): fruit and vegetable scraps, coffee grounds, fresh grass clippings, garden trimmings
If you are unsure about an item, check the A-Z list of what you can compost. The short version: skip meat, fish, dairy, cooking oil, diseased plants and pet waste.
Step 1: Pick a site
Choose a level spot on bare soil, in part shade, within easy reach of the kitchen and a hose. Those four things matter most.
- Bare soil, not concrete. Excess water drains away, and worms and soil life can move in from below.
- Part shade. Full summer sun dries the pile out. Deep shade keeps it cold.
- Close enough to use. A pile at the far end of the yard gets ignored in February. You want the walk from the kitchen to feel easy in bad weather.
- Away from fences and walls you care about. Damp compost against a wooden fence or the house siding will rot it. Leave about 1-2 ft (30-60 cm) of space.
- Check local rules. Some cities and HOAs require an enclosed bin, or set minimum distances from property lines.
Clear grass and weeds from the footprint and loosen the soil with a fork. You do not need to dig deep.
Step 2: Decide on size
Aim for a pile roughly 3x3x3 ft (1 m cube). That is the size most university extension guides recommend as a minimum for a pile that heats up.
Smaller piles still compost. They just stay cooler and take longer. Piles much bigger than about 5x5x5 ft (1.5 m cube) are hard to turn by hand and can go airless in the center.
You do not have to build it all in one day. Many people start with a base layer and build up over weeks as scraps and yard waste arrive. A pile built all at once, though, heats faster. If you have a big load of leaves and grass on hand, use it.
Step 3: Lay a base of coarse browns
Start with 4-6 inches (10-15 cm) of coarse, woody material. Small twigs, chopped woody stems, corn stalks, straw or wood chips all work.
This layer does two jobs. It lets air flow up into the bottom of the pile, and it stops the base from sitting in a puddle after heavy rain. Without it, the bottom of a pile often turns into a dense, wet, sour layer.
Step 4: Add browns and greens
Build the pile with roughly 2-3 parts browns to 1 part greens by volume. You can layer them or mix them. Mixing works a little better; layering is easier to keep track of.
| Layer | Material | Thickness (approx.) | Tip |
|---|---|---|---|
| Base | Coarse browns: twigs, stalks, wood chips | 4-6 in (10-15 cm) | Keeps air flowing and water draining |
| Browns | Leaves, straw, shredded cardboard | 4-6 in (10-15 cm) | Shred or break up big pieces |
| Greens | Kitchen scraps, grass clippings, coffee grounds | 2-3 in (5-8 cm) | Spread thin; thick grass mats go slimy |
| Optional | Garden soil or finished compost | A few shovelfuls | Adds microbes; not essential |
| Repeat | Browns, then greens | Up to about 3 ft (1 m) | Always finish with a layer of browns |
Two habits make a big difference:
- Cover every addition of kitchen scraps with browns. A layer of leaves or straw on top hides food from flies and animals and cuts down on smell.
- Chop large items. Whole melons, cabbage stalks and thick stems take far longer to break down. A few cuts with a spade speeds them up.
If you have more greens than browns, the pile will get wet and smelly. If you have more browns than greens, it will sit there and do very little. Most home piles lean too far toward greens in summer and too far toward browns in fall. Stockpiling a few bags of fall leaves to mix with summer greens fixes the more common of the two. The compost calculator can help you balance a specific mix.
Step 5: Water it
Water each layer as you build, not just the top. Dry browns in particular need a real soaking. The target is like a wrung-out sponge, roughly 40-60% moisture.
The squeeze test is the easiest check. Grab a handful from inside the pile and squeeze hard.
- A few drops come out: perfect
- Nothing comes out and it crumbles: too dry, add water
- Water streams out: too wet, add browns and turn
A new pile of dry leaves and straw can take a surprising amount of water. Keep going until the squeeze test passes in the middle, not just on the surface.
Step 6: Your first month, week by week
A new pile changes quickly in the first few weeks. Here is roughly what to expect and what to do.
| Week | What you will see | What to do |
|---|---|---|
| Week 1 | Pile may warm up within 2-5 days; slight earthy or sweet smell; greens start to wilt | Check moisture with the squeeze test; keep adding scraps and covering with browns |
| Week 2 | Middle feels warm or hot if the pile is big and balanced; volume starts to shrink | Turn the pile: move outside material to the middle; water any dry patches |
| Week 3 | Scraps are soft and hard to recognize in the center; white fungal threads may appear | Keep adding, keep covering; check moisture after dry or rainy spells |
| Week 4 | Pile has shrunk noticeably, often by a quarter to a third; center is darker | Turn again; decide whether to keep adding or close this pile and start a second one |
If the pile never warms up, it usually needs more greens, more water or more volume. If it smells like rotten eggs or ammonia, it is too wet or too green; see why does my compost smell.
Keeping it going after the first month
After the first month, the routine is simple:
- Add scraps and cover them with browns
- Check moisture every week or two, more often in hot, dry weather
- Turn every 1-2 weeks if you want faster results; every month or two is fine if you do not
At some point, you will want to stop adding to the pile so it can finish. Many gardeners start a second pile next to the first at this point. The first pile finishes while the second one fills. That is the logic behind the three-bay system in our bin vs tumbler vs pile comparison.
A well-managed pile turned regularly is usually ready in about 2-6 months. A pile left alone can take 6-24 months. Both end up in the same place.
Common first-pile mistakes
Most new piles that fail share one of a few problems. All of them are easy to fix.
- Too small. A knee-high heap stays cold. Build up to about 3 ft (1 m) before judging it.
- Too dry. Dry leaves and straw shed water. Soak each layer, then do the squeeze test in the middle.
- Only kitchen scraps. Scraps alone turn wet and sour. Every bucket of greens needs two or three buckets of browns.
- Food left on top. Exposed scraps attract flies, raccoons and rats. Always bury them or cover them with browns.
Next step
Once your pile is running, read how long compost takes to plan your first harvest. If you want to speed things up, hot composting shows how to push a pile to finish in about 1-3 months.
Frequently asked questions
What do I put at the bottom of a compost pile?
A 4-6 inch (10-15 cm) layer of coarse browns such as small twigs, woody stems, corn stalks or wood chips. It lets air in from below and helps excess water drain.
Should a compost pile be in sun or shade?
Part shade is ideal. Full sun dries a pile out fast in summer, and deep shade keeps it cold and slow. Easy access matters more than perfect light.
Do I need to add soil or an activator to start a compost pile?
No. A few shovels of garden soil or finished compost add microbes and can help a new pile get going, but greens and browns already carry plenty. Commercial activators are optional.
How often should I turn a new compost pile?
Every 1-2 weeks is plenty for a home pile. Turning more often speeds it up; never turning still works, it just takes longer, often 6-24 months.
How big should a compost pile be?
Aim for roughly 3x3x3 ft (1 m cube). That is large enough to hold heat but small enough to turn by hand. Piles much bigger than 5 ft (1.5 m) can get airless in the middle.
Can I start a compost pile in winter?
Yes. It will sit mostly dormant until spring, but you can keep adding material. See our guide to composting in winter.
Should I cover my compost pile?
A loose cover such as a tarp, old carpet or a layer of straw helps in very wet or very dry climates. It keeps rain from waterlogging the pile and stops the top from drying out.