This aligns with Kenya’s long rains (Mar–May) and short rains (Oct–Dec) cycle. Adjust ±1 month depending on altitude.

☕ Coffee Husbandry & Fertilization Calendar (Kenya – Arabica)

🌱 1. Post-Harvest & Recovery Phase (Jan–Feb)

🎯 Objective:

Rebuild tree energy & prepare new fruiting wood.

Field Activities:

• Structural pruning (remove 3-year-old primaries)
• Remove suckers & deadwood
• Soil testing (macro + micro)
• Apply compost or well-decomposed manure (20–25 kg/tree)

🧪 Fertilization (Soil Correction Phase)

If pH < 5.2:

• Apply agricultural lime: 1–2 kg/tree (once every 2–3 years)

Basal Application (Recovery Feed):

• NPK 17:17:17 → 150 g/tree
  OR
• 100 g DAP + 50 g CAN (if soil P is low)

Why now? Tree is rebuilding leaf area → requires nitrogen for vegetative growth.

🌸 2. Pre-Flowering & Flower Initiation (Mar–April – Long Rains)

🎯 Objective:

Strong flowering & root expansion.

Fertilization Schedule:

Soil Application (Early Rain Onset):

• NPK 23:23:0 or 20:20:0
• 150–200 g/tree

Foliar Spray:

• Boron (B) + Zinc (Zn)
• Spray at 50% flowering

⚠️ Boron improves fruit set → directly impacts AA bean count.

🍒 3. Berry Expansion Phase (May–August)

🔥 This is the most critical window for AA/AB size and 820–850 g/L density.

🎯 Objective:

Maximize cherry size & density.

Primary Nutrient Focus:

• Nitrogen (N)
• Potassium (K₂O)

🌿 Customized Fertilization (Size Phase)

Split Application (2 rounds):

Round 1 (Fruit Expansion Start)

• NPK 26:5:5 → 200 g/tree

Round 2 (6–8 weeks later)

• MOP (Muriate of Potash 60% K₂O)
  → 100 g/tree

OR

• NPK 15:5:30 (high potassium blend)

Why Potassium?

Potassium:

• Regulates water movement
• Increases bean filling
• Improves density (g/L)
• Boosts sugar (Brix)

Without adequate K during this stage → small beans, low density, more “lights.”

🛡 Disease Management (Critical During Expansion)

• Spray Copper fungicide (prevent CLR)
• Monitor CBD during cool wet spells
• Set CBB traps
• Maintain clean “plate” under canopy

🍂 4. Ripening & Maturation (Sept–Nov)

🎯 Objective:

Uniform ripening & sugar development.

Fertilization:

Foliar Spray:

• Calcium + Boron
• Zinc (light dose)

Avoid heavy nitrogen now → prevents delayed ripening.

📊 Summary Fertilization Table (Per Tree Annual Guide)

🌍 Soil Health Support Strategy

For small-scale farmers (1 acre ≈ 1,000–1,100 trees):

• Annual composting program
• Mulch at start of dry season
• Test Electrical Conductivity (EC) to avoid salt buildup
• Maintain pH 5.5–6.5

📌 Yield & Quality Outcome (If Followed Correctly)

✔ AA/AB 65–75% screen out
✔ Density 820–850 g/L
✔ Improved cup sweetness
✔ Reduced floaters
✔ Lower CBB damage
✔ Stronger leaf retention

🧠 Advanced Recommendation (Kenya Coffee School Model)

For farmers under structured programs like those developed by Alfred Gitau Mwaura, integrate:

• Soil lab data-driven fertilization
• Farm-level Brix testing
• Digital record keeping per block
• Input timing tied strictly to rainfall events