Greens (Nitrogen Sources)
Material (C:N ratio)
Pounds
Browns (Carbon Sources)
Material (C:N ratio)
Pounds
Compost C:N Ratio Guide
- Ideal ratio: 25–35:1 C:N. The classic target is 30:1.
- Below 20:1 (too many greens) = smelly, slimy pile. Add more browns.
- Above 40:1 (too many browns) = slow decomposition, little heat. Add more greens.
- Keep it moist like a wrung-out sponge. Too dry and decomposition stops; too wet and it goes anaerobic and stinks.
- Turn it every 1–2 weeks to add oxygen. Hot compost (130–160°F) finishes in 4–8 weeks.