1. Objectives
By the end of this lesson, participants will be able to:
- Understand nutrient requirements of Aquilaria at each growth stage.
- Design organic fertilizer schedules for seedlings, juvenile trees, and mature stands.
- Implement sustainable soil enrichment strategies aligned with agroforestry systems.
- Apply science-based practices that enhance tree vigor, lignin formation, and resin response potential.
2. Nutrient Requirements of Aquilaria
Aquilaria species generally require:
- Nitrogen (N) – vegetative growth, canopy expansion
- Phosphorus (P) – root development, early establishment
- Potassium (K) – stress resistance, disease tolerance, cell integrity
- Secondary nutrients: Ca, Mg, S
- Micronutrients: Fe, Mn, B, Zn, Cu, Mo
Key Principle:
Aquilaria responds best to mild, slow-release, organic nutrient sources—not high-salt chemical fertilizers.
3. Organic Fertilizer Options
- A. Base Soil Amendments
- Vermicompost / Humus: improves structure and microbial activity
- Well-decomposed animal manure: cow, goat, poultry litter
- Cocopeat / Rice hull: better aeration, moisture retention
- Carbonized rice hull (CRH): increases CEC, potassium, and potassium silicate
- Biochar: enhances soil buffering, long-term carbon storage
- B. Specialty Organic Inputs
- Seaweed/Kelp Extract: source of natural growth hormones
- Fish Amino Acid (FAA)
- Fermented Plant Juice (FPJ)
- CalPhos (Calcium Phosphate)
- Bone meal / Rock phosphate
- Potash-rich sources: banana peel compost, wood ash (in controlled amount)
- Trichoderma-enriched compost — boosts soil microbiome
4. Organic Fertilizer Schedules for Agarwood
A. Nursery / Seedling Stage (0–6 months)
Frequency: Every 2 weeks
| Input | Rate | Notes |
|---|---|---|
| Vermicompost tea | 1:20 dilution | Sprench or foliar |
| FAA or FPJ | 5–10 mL/L | Improves vigor |
| Seaweed extract | 5 mL/L | Roots + stress tolerance |
| Trichoderma inoculation | once every 2 months | Disease prevention |
Goal: Produce vigorous seedlings with strong roots, ready for field hardening.
B. Juvenile Stage (6 months–2 years in field)
Frequency: Every 45–60 days
| Input | Rate per tree | Notes |
|---|---|---|
| Vermicompost | 0.5–1 kg | Mixed in dripline |
| CRH + Biochar mix | 200–300 g | Soil aeration, K supply |
| Cow/Goat manure | 1–2 kg | Slow-release nutrition |
| CalPhos | 50–100 g | Root and branch formation |
| Banana-peel compost | 200 g | Natural potash |
Goal: Fast canopy development, diameter expansion, and healthy lignin-rich wood formation.
C. Pre-Induction Mature Trees (2–5 years)
Frequency: Every 3 months
| Input | Rate per tree | Notes |
|---|---|---|
| Vermicompost | 1–2 kg | Enhances soil microbes |
| Biochar | 500 g | Carbon & nutrient retention |
| Organic N sources (legume biomass, manure) | 1–3 kg | Promotes vigor |
| Multi-micronutrient blend | 50–100 g | Prevents deficiency |
| Mycorrhiza/perlite | As per label | Enhances nutrient uptake |
Goal: Build woody biomass and strong immune response before inoculation.
D. Post-Induction Trees (after F. oxysporum or enzyme/bioleaching inoculation)
Frequency: Every 3–4 months
| Input | Rate | Purpose |
|---|---|---|
| Low-N, High-K organic mix | 1–2 kg | Enhances resin pathways |
| Wood ash (controlled) | 100–150 g | Boosts phenolic synthesis |
| Biochar + compost | 1–2 kg | Supports microbial balance |
| Mn-/Fe-rich organic amendments | 20–50 g | Supports oxidation reactions |
| Avoid high nitrogen | — | Nitrogen > stimulates vegetative growth instead of resin |
Goal: Support resin induction, stress balance, and controlled defense metabolism.
5. Sustainable Soil Enrichment Techniques
- A. Green Manuring
- Plant nitrogen-fixing species:
Sesbania grandiflora, Gliricidia sepium, Erythrina variegata - Incorporate prunings into soil every 3–4 months
- Plant nitrogen-fixing species:
- B. Compost Application
- Maintain 2–3 cm compost mulch around each tree
- Add new compost 3 times per year
- C. Microbial Enrichment
- Use Trichoderma, mycorrhiza, and Bacillus subtilis
- Increases nutrient uptake and suppresses pathogens
- D. Mulching Systems
- Rice straw, kakawate leaves, coconut husk chips
- Retains moisture, reduces weeds, increases organic carbon
6. Recommended Annual Fertilization Calendar
January–February: Biochar, compost, manure, CalPhos, Trichoderma
April–May (Dry season): Vermicompost tea, FPJ, watering + mulching
July–August (Rainy season peak): Manure + compost mix, micronutrients
Apply weeding and soil aeration
October–November: CRH, potash compost, seaweed extract
Prepare for dry months
7. Indicators of Proper Fertility Management
- Steady diameter increment (≥1–1.5 cm/year)
- Dark green leaves, no chlorosis
- Stable branching pattern
- Good root mass and soil friability
- Reduced pest/disease incidence
- Higher resin response after inoculation