Carbon-to-nitrogen ratios for common compost materials — print and keep at the pile.
| Material | C:N Ratio | Notes |
|---|---|---|
| 🟢 GREENS (Nitrogen-rich) | ||
| Grass clippings (fresh) | 12–20:1 | Mix to avoid matting |
| Food scraps / veg waste | 15–20:1 | Bury to deter pests |
| Coffee grounds | 20:1 | Mildly acidic |
| Chicken manure | 7:1 | Very hot — dilute well |
| Cow / horse manure | 20:1 | Excellent activator |
| Legume residues | 15–30:1 | Peas, beans, clover |
| Fresh seaweed | 20:1 | Rinse salt first |
| 🟤 BROWNS (Carbon-rich) | ||
| Autumn leaves | 40–80:1 | Shred to speed breakdown |
| Straw / hay | 40–100:1 | Excellent bulking agent |
| Cardboard (plain) | 350–500:1 | Remove tape/staples |
| Sawdust (untreated) | 200–500:1 | Avoid treated wood |
| Wood chips | 200–700:1 | Best for slow composting |
| Newspaper | 170:1 | Shred; soy ink only |
| Corn stalks | 60:1 | Chop to 2–3 inch pieces |