Composting turns kitchen scraps, yard waste and leaves into a dark, crumbly material that improves almost any garden soil. It reduces what you send to the landfill, saves money on soil amendments and closes the loop between your kitchen and your garden.
You do not need special skills or expensive equipment. This guide explains the basics, how to choose a system and how to fix common problems.
How Composting Works
Composting is controlled decomposition. Microorganisms such as bacteria and fungi, along with larger organisms like worms and insects, break down organic matter. To do their job well, they need four things:
- Carbon (from “browns”)
- Nitrogen (from “greens”)
- Moisture
- Oxygen
Balance these, and your pile will break down steadily without bad smells.
Greens and Browns
Greens (Nitrogen-Rich)
- Fruit and vegetable scraps
- Coffee grounds and paper filters
- Tea leaves and bags (remove staples; some bags contain plastic)
- Fresh grass clippings
- Fresh plant trimmings
- Manure from herbivores such as rabbits, chickens or horses (not dogs or cats)
Browns (Carbon-Rich)
- Dry leaves
- Straw
- Shredded newspaper and plain cardboard
- Paper towels and napkins (if not greasy or contaminated with chemicals)
- Wood chips and sawdust from untreated wood, in moderation
- Dried plant stalks
Finding the Balance
A common guideline is to use more browns than greens by volume, often around two or three parts browns to one part greens. Do not worry about precision. If the pile is wet and smelly, add browns. If it is dry and not breaking down, add greens and water.
What Not to Compost at Home
- Meat, fish, bones and dairy: Can attract pests and create odors in home systems
- Oils and greasy foods
- Pet waste from dogs and cats: May contain harmful pathogens
- Diseased plants: Home piles may not get hot enough to kill disease organisms
- Weeds with seeds or aggressive roots: May survive and spread
- Treated wood, coal ash or charcoal briquette ash
- Glossy or coated paper
- Plastics and “compostable” plastics unless your system is designed for them, since many require industrial facilities
Some communities offer curbside or drop-off composting that accepts more materials. Check local programs.
Choosing a Composting System
Open Pile
Simply pile materials in a corner of the yard.
- Pros: Free and easy; handles large volumes.
- Cons: Can look messy; may attract animals if food scraps are exposed.
Enclosed Bin
Plastic, wood or wire bins contain the pile.
- Pros: Neater, more protection from pests, retains heat and moisture.
- Cons: Harder to turn; limited volume.
Many municipalities sell discounted compost bins. Check your local government’s website.
Tumbler
A barrel that rotates on a frame.
- Pros: Easy to turn, enclosed, can produce compost quickly when conditions are right.
- Cons: Smaller capacity; can be heavy when full; materials can get too wet.
Worm Composting (Vermicomposting)
A bin of red wiggler worms that eat food scraps.
- Pros: Works indoors or in small spaces; produces rich worm castings.
- Cons: Requires attention to moisture, temperature and feeding.
Bokashi
A fermentation process using inoculated bran in an airtight bucket. Fermented material is then buried or added to a compost pile.
- Pros: Accepts some materials traditional home composting avoids; compact.
- Cons: Requires ongoing purchase of bran and a second step to finish.
How to Start a Compost Pile
Step 1: Pick a Location
Choose a level, well-drained spot with easy access from the kitchen and garden. Partial shade helps prevent the pile from drying out in hot climates.
Step 2: Start With Browns
Lay down a layer of coarse browns, like small twigs or straw, to help airflow.
Step 3: Add Greens and Browns in Layers
Alternate greens and browns, or mix them together. Bury food scraps in the center and cover with browns to discourage pests and reduce odors.
Step 4: Keep It Moist
Aim for the dampness of a wrung-out sponge. Add water during dry spells and browns if it gets soggy.
Step 5: Turn It
Turning adds oxygen and speeds decomposition. Many gardeners turn every week or two with a garden fork. If you do not turn at all, the pile will still break down, just more slowly (sometimes called “cold composting”).
Step 6: Let It Finish
Depending on materials, size, moisture and turning, compost can take anywhere from a couple of months to a year or more.
Hot vs. Cold Composting
Hot Composting
A larger, well-balanced pile, often around 3 feet in each direction or larger, can heat up significantly as microbes work. Hot piles break down faster and can kill many weed seeds and pathogens when temperatures stay high enough long enough. Hot composting requires more effort and regular turning.
Cold Composting
Add materials as you have them and let nature take its time. It requires less work but takes longer, and weed seeds may survive.
Troubleshooting
| Problem | Likely cause | Fix |
|---|---|---|
| Smells like ammonia | Too many greens | Add browns and turn |
| Smells rotten | Too wet or not enough air | Add browns, turn, improve drainage |
| Not breaking down | Too dry, too many browns or pile too small | Add water and greens, turn, add more material |
| Attracting animals | Exposed food scraps or non-compostable foods | Bury scraps, avoid meat and dairy, use an enclosed bin |
| Fruit flies | Exposed food scraps | Cover with browns; keep indoor container closed |
How to Tell When Compost Is Ready
Finished compost:
- Is dark brown and crumbly
- Smells earthy, not sour or rotten
- Contains few recognizable food scraps
Some larger pieces may remain. Sift them out with a screen and return them to the pile.
How to Use Compost
- Mix into garden beds before planting.
- Top-dress existing beds and raised beds each season.
- Side-dress vegetables during the growing season.
- Mulch around trees and shrubs, keeping it away from trunks.
- Add to potting mixes in moderation.
- Spread a thin layer on lawns.
Compost improves soil structure, water retention and microbial life. For specific nutrient needs, see how to test and improve garden soil.
Frequently Asked Questions
How long does it take to make compost?
Anywhere from a couple of months for an actively managed hot pile to a year or more for a cold pile.
Can I compost in an apartment?
Yes. Worm bins and bokashi systems work well in small spaces. Some communities also offer drop-off sites.
Should I add compost starter?
Most piles do not need it. A shovelful of garden soil or finished compost can introduce helpful microbes.
Can I compost in winter?
Decomposition slows in cold weather but resumes in spring. Keep adding materials and turn when possible.
Is it okay to compost citrus and onions?
In a regular compost pile, small amounts are generally fine. Worm bins may need these limited, as worms tend to avoid them.
The Bottom Line
Composting is simple: balance greens and browns, keep the pile moist and give it air. Choose a system that fits your space and routine, avoid problem materials and use your finished compost to feed your garden. Your soil, your plants and your trash can will all benefit.
Editorial note: Backyard Bloomer is independent and reader-supported. This guide is based on research into manufacturer documentation, published specifications and widely accepted best practices; we have not been paid to mention any product. If we add affiliate links in the future, they will be clearly disclosed per our Affiliate Disclosure.