Pak Choy (Sawi)
Brassica rapa var. chinensis
Malay names: Sawi, Pak Choy
Very fast leafy brassica ideal for beginners; reliable in NFT/DWC under shade net.
🌞 Light & Temperature
Light: Bright light to partial sun (4–6 h)
Temperature: 20–32°C
🪴 Container & Medium
Container: NFT/DWC/raft; 2 inch net pots; 15–30 L reservoir per 8–12 plants.
Medium / Solution: Medium: clay pebbles/rockwool; Solution: pH 5.8–6.5, EC 1.5–2.0 mS/cm
💧 Watering / Solution Maintenance
Schedule: Top-up daily; full change every 7–10 days
Top-up: Maintain EC at target; top-up with water first
Target pH 5.8–6.5; EC 1.5–2.0 mS/cm. Strong aeration reduces root issues.
🧪 Nutrients
Type: A+B vegetable nutrient with micronutrients
Frequency: Adjust EC/pH 2–3x/week; full change 7–10 days
Dosage/EC: EC 1.5–2.0 mS/cm; maintain pH 5.8–6.5
🍓 Harvest
Start: 4–6 weeks from sowing
Seasonality: Year-round; best with shade and airflow in wet season
Duration: 2–3 week harvest window
Harvest Indicators: Rosettes 15–25 cm; leaves tender and glossy
Tips: Harvest whole or outer leaves for continuous picking.
🌱 Propagation
Seeds; thin to one plant per site.
🐛 Pests & Diseases
- Caterpillars: Netting; hand-pick; BT bio-insecticide as needed.
- Aphids: Neem 1%; wash undersides; encourage predators.
🌦️ Seasonal Notes (Malaysia)
Provide rain cover or gutters to reduce splash diseases during monsoon.
📝 System Notes
Space 20–25 cm; avoid overcrowding for airflow.
💡 Extra Care Tips
- Keep channels clean to prevent pythium
- Harvest before bolting in hot spells
Note
EC and pH are guidelines—adjust to plant response and your water source. In monsoon humidity, increase airflow and reduce overcrowding to limit disease.