How to grow tatsoi
Overview
Tatsoi (Brassica rapa subsp. narinosa) is a cool-season Asian green grown for its spoon-shaped leaves that form a flat rosette. It is prized for its mild mustard flavour and exceptional cold tolerance, making it a reliable crop for autumn and winter gardens. Success hinges on consistent moisture and protection from heat that triggers bolting.
Varieties
- Tatsoi (Standard) — The classic green rosette variety, widely available in Australian seed catalogues and very frost-hardy.
- Red Leaf Tatsoi — A colourful variant with burgundy-tinged leaves that adds visual interest to salads and has similar cold tolerance.
Soil Preparation
Tatsoi prefers well-drained, fertile soil with a pH of 6.0–7.0. Enrich the bed with well-rotted compost or aged manure before sowing to provide steady nutrients. Ensure good drainage to avoid root rot; raised beds are ideal in heavy clay areas.
Growing Guide
Sow tatsoi seeds directly 5 mm deep, spaced 20–25 cm apart in rows 30 cm apart. It thrives in full sun during cool months but benefits from light shade in warmer weather. Keep soil consistently moist but not waterlogged, and mulch to retain moisture and keep roots cool. Succession sow every 2–3 weeks for a continuous harvest. Thin seedlings to prevent overcrowding and promote healthy rosette formation.
Sowing
Direct sow seed 5 mm deep, spaced 20–25 cm apart; germination takes 4–7 days at 10–20°C. Thin to final spacing when seedlings have 2–3 true leaves. Transplants can be started in punnets then moved out at 4 weeks, but direct sowing is simpler and reduces root disturbance.
Care
Feed with a balanced liquid fertiliser (e.g., seaweed or fish emulsion) every 2–3 weeks during active growth. Remove yellowing or damaged outer leaves promptly to improve air circulation and reduce disease risk. Lightly cultivate soil around plants to control weeds without disturbing shallow roots.
Companion Planting
Grow tatsoi with lettuce, radish, spinach, peas, or onions – these share similar watering needs and do not compete heavily. Avoid planting near other brassicas (e.g., broccoli, kale) to reduce pest and disease pressure, and keep strawberries away as they can hinder growth.
Common Pests & Risks
Common pests include flea beetles (small holes in leaves), aphids (clustered on undersides), and caterpillars (chewed edges). Control with fine insect netting, apply neem oil or insecticidal soap for aphids, and hand-pick caterpillars. Diatomaceous earth can deter flea beetles. Rotate crops to prevent soil-borne diseases.
Harvesting
Begin harvesting outer leaves when they reach 10–15 cm long, or cut the entire rosette at soil level after 6–8 weeks. Young leaves are tender for salads, while larger leaves suit stir-fries. Regular harvesting encourages new growth from the centre.
In the Kitchen
Use tatsoi raw in salads for a mild, peppery kick, or lightly sauté in stir-fries and soups until just wilted. It retains texture better than spinach when cooked. Store unwashed leaves in a sealed bag in the fridge for up to 5 days.
Troubleshooting
Yellow leaves: overwatering or nitrogen deficiency – reduce watering and apply a balanced fertiliser. Bolting: heat or stress – harvest promptly and shade plants if warm weather hits. Holes in leaves: flea beetles – cover with insect netting early. Curled leaves: aphids – spray undersides with insecticidal soap. Damping off: avoid overwatering and ensure good air circulation.