How-to Guide
How to Start Composting at Home
The short answer
Build a compost pile from roughly two to three parts 'browns' (dry, carbon-rich: dead leaves, shredded cardboard, straw) to one part 'greens' (moist, nitrogen-rich: veg scraps, coffee grounds, grass clippings). Layer them, keep the pile about the size of a cubic yard (3 ft x 3 ft x 3 ft), and keep it as damp as a wrung-out sponge.
That ratio and size are what let the pile heat up and break down instead of turning into a cold, smelly heap. Turn it every week or two for air; if it smells sour it needs more browns and air, and if it's dry and inactive it needs water and more greens.
Browns and greens
- Browns (carbon): dry leaves, shredded paper/cardboard, straw, wood chips, sawdust.
- Greens (nitrogen): fruit and vegetable scraps, coffee grounds, fresh grass clippings, plant trimmings.
- Aim for about 2-3x as much brown material as green by volume.
Build it right
- 1Start with bulky browns — A base layer of coarse material (small branches, corn cobs) lets air in from the bottom.
- 2Layer greens and browns — Alternate a layer of greens with two of browns; finish with browns on top to hold in smell and keep pests out.
- 3Size it — A pile roughly 3 ft x 3 ft x 3 ft holds enough mass to heat up; much smaller won't cook.
- 4Keep it damp and turned — Moist like a wrung-out sponge; turn every 1-2 weeks to add air and speed things up.
Do not compost
- Meat, dairy, greasy or oily food (pests and odor).
- Pet waste from dogs/cats.
- Diseased plants or weeds gone to seed (a home pile may not get hot enough to kill them).
→ A healthy pile smells earthy, not rotten. Sour smell = too wet / not enough air / too many greens → add browns and turn it.
Sources
Reviewed 2026-07-18. We cite university Extension, government, and established horticultural sources — and never invent pesticide rates or dangerous treatments.
- University of New Hampshire Extension — Composting for the Home Gardener — A working compost pile balances carbon-rich 'browns' and nitrogen-rich 'greens', is built at least about one cubic yard (3x3x3 ft) to hold heat, kept as moist as a wrung-out sponge, and turned for aeration; meat, dairy, and pet waste are excluded.