Bocashi
Sources: Manual de producción de insumos orgánicos by MAOES (2022)
Bocashi is an organic fertilizer produced by aerobic fermentation of organic residues in the presence of air (oxygen) by microbial populations found in the residues and waste materials themselves. It both fertilizes plants and nourishes the soil. (source: MAOES ∙ Manual de producción de insumos orgánicos.pdf)
Advantages
- No toxic gases or bad odours when properly managed
- Scalable — produced in small or large volumes
- Self-regulates pathogenic agents through biological inoculation
- Quickly available as crop nutrition at very low cost
- Converts farm and crop waste (including coffee pulp and parchment) into plant nutrition
Key Ingredients and Their Functions
| Ingredient | Function |
|---|---|
| Charcoal | Houses microorganisms; retains moisture and nutrients; converts to humus; buffers root-zone temperature |
| Rice bran / maize flour | B vitamins for fermentation; silicon, phosphorus, potassium, calcium, magnesium |
| Molasses / cane honey | Energy for fermentation; potassium, calcium, phosphorus, magnesium; micro-nutrients (boron, zinc, manganese, iron) |
| Chicken manure / cattle manure | Primary nitrogen source; phosphorus, potassium, calcium, magnesium, iron, manganese, zinc, copper, boron |
| Rice husks | Improves texture and aeration; stimulates root development; increases pest resistance (silicon); converts to humus |
| Aged bocashi | Microbial inoculant to initiate and complete fermentation |
| Rock flour | Mineral remineralization |
| Activated MM | Enriches microbial diversity and quality |
Note for coffee farms: Coffee pulp (pulpa de café) and parchment (pergamino) are explicitly listed as suitable substitutes for rice husks, making bocashi directly applicable to wet processing byproducts. (source: MAOES ∙ Manual de producción de insumos orgánicos.pdf)
Standard Recipe (10 bags of bocashi)
- 4 bags chicken manure
- 3 bags rice husks (or coffee pulp/parchment)
- 1 qq aged bocashi
- 1 qq rock flour
- 1 qq charcoal
- 1 gallon molasses
- 1 barrel activated MM
15-Day Process
- Layer all materials in piles 1m wide, repeat layers until materials are exhausted
- Mix thoroughly using two shovels simultaneously
- Add water (with molasses dissolved) — moisture test: fist should hold together but release no drops
- Heap to 1.5m height, cover with sacks (creates initial heat shock)
- Day 2 onward: Temperature can reach 70°C — turn twice daily (morning and afternoon), days 2–5
- Day 3: Must spread pile to max 30cm height to prevent overheating; remove cover sacks
- Days 6–12: Turn once daily
- Day 13: Ready to use or store in nylon sacks in a dry, shaded place for up to 2 months
Temperature monitoring: Use a thermometer or the “machete test” — insert for 3–5 minutes; if you can hold it without pain, temperature is acceptable; if it burns, turn the pile immediately.
8-Day Japanese Method (No Turning)
An innovation validated by Costa Rican organic producers. The same ingredients are bagged and stacked on wooden slats for aeration, covered in plastic, and left 8 days. Temperature should not exceed 60°C. Ready on day 8.
Application Dosage
| Use | Dosage |
|---|---|
| Seedling nurseries (1–2 month bocashi) | 1–4 parts bocashi to 6–9 parts sieved soil |
| Tree bags | 50% soil + 50% bocashi |
| At transplant (into planting hole) | ¼ to ½ lb per plant (keep roots from touching directly) |