Soil Science
Thermal Composting
Composting is not a rubbish heap; it is aerobic bioreactor management. Success relies entirely on moisture, oxygen, and the Carbon to Nitrogen (C:N) ratio.
The C:N Ratio
Microbes require carbon for energy and nitrogen for protein synthesis. The optimal ratio is 25-30 parts carbon to 1 part nitrogen by weight.
Common Mistakes
- Too much nitrogen (grass clippings) leading to anaerobic putrefaction (it smells bad).
- Too dry: microbes cannot function without a moisture film. Target is 50-60% moisture (like a wrung-out sponge).
Data Points
| Material | Approx C:N Ratio |
|---|---|
| Grass Clippings (N) | 15:1 |
| Autumn Leaves (C) | 60:1 |
| Woodchip (C) | 400:1 |
| Coffee Grounds (N) | 20:1 |
FAQ
Do I need to turn it?
Yes. Turning introduces oxygen, keeping the process aerobic and maintaining high temperatures.
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