Mizuna & Mibuna

Mizuna (Brassica rapa var. nipposinica) and Mibuna (Brassica rapa var. nipposinica) are Japanese brassica leaf crops that have become indispensable in UK kitchen gardens. Mizuna is the more widely grown: its deeply pinnate, feathery leaves with rounded lobes have a refreshing, mild peppery flavour that works equally well in salads and stir-fries. Mibuna produces smooth, undivided, strap-shaped leaves with a more assertive, mustard-influenced flavour. Red and purple-leaved varieties of mizuna add striking colour to both the garden and the plate. All types are fast, productive, and far more tolerant of autumn cold than most salad crops — autumn sowings from August to September produce some of the finest salad leaf of the entire year.

Mizuna seed is now widely available from most UK seed companies and garden centres. The standard green mizuna is widely stocked. Named varieties including Red Frills, Kyona, and Red Knight are best found through specialist online seed companies. Mibuna is less commonly stocked but is available from oriental vegetable specialists and several general seed companies. Mixed oriental salad leaf packets often include both mizuna and mibuna as components — a useful way to try several types at once.

☀️ Shade Seedling Trays in Hot Spells

Young seedling trays are far more vulnerable to heat stress than established plants — direct sun on a hot day can scorch or bolt seedlings within hours. Move trays to a shaded spot during the hottest part of the day until they're established enough to go out, especially for sowings made in high summer.

🐛 Flea Beetle Protection

Flea beetle (Phyllotreta species) is the primary pest of mizuna, mibuna, and all oriental brassica crops. The tiny metallic black beetles create characteristic round shothole damage in leaves — seedlings can be badly damaged within 48 hours of emergence in hot, dry weather. Fine insect-proof mesh (0.8mm aperture or finer) applied immediately at sowing is the most effective and reliable control. Remove for harvesting and replace promptly. Flea beetle is worst in spring and early summer; autumn sowings from August suffer far less damage as beetle populations decline. Module-raised transplants at 5–7cm tall are more resilient than direct-sown seedlings.

💧 Watering

Consistent moisture is important for preventing premature bolting and maintaining the quality of mizuna's delicate leaves. Water every 5–7 days for established plants in dry weather — more frequently for young seedlings and container-grown plants. Drought stress in midsummer causes rapid bolting and produces tough, more bitter leaves. A mulch of garden compost around established plants significantly reduces watering frequency. Container-grown mizuna needs daily watering in warm weather as containers dry out rapidly in summer heat.

✂️ Harvesting

Mizuna is one of the most productive cut-and-come-again crops in the kitchen garden — each plant typically regrows 3–5 times after cutting before quality declines. Cut with scissors 3–5cm above the soil surface, never pulling plants up. The stumps regrow from the base within 10–14 days. For the best leaf quality, harvest before plants exceed 15–20cm — older, larger leaves become more pungent and slightly tough. Pick regularly even if you cannot use all the harvest — frequent cutting stimulates regrowth and prevents bolting. A bowl of mixed mizuna and mibuna leaves harvested in the morning is at peak flavour.

🧊 Refrigerator Storage

Store mizuna and mibuna leaves dry and unwashed in a breathable bag or loosely closed container in the salad drawer. Do not wash before refrigerating — moisture dramatically shortens leaf life. Fresh-picked mizuna keeps for 3–4 days refrigerated. To revive slightly wilted leaves, submerge briefly in cold water for 5 minutes, shake dry, and use immediately. Store mibuna separately from mizuna if possible — its stronger flavour can transfer to the milder mizuna leaves over time.

🥗 Using Fresh in Salads

Mizuna is most often eaten raw in mixed salad leaves where its mild, refreshing peppery flavour lifts the whole bowl without dominating. Baby leaves are finest raw. Young mizuna needs only a simple dressing of good olive oil, lemon juice, and sea salt. A classic Japanese sesame dressing — toasted sesame oil, rice vinegar, soy sauce, and a little sugar — is outstanding with mizuna. Mix with rocket for a more complex peppery flavour, or with mild lettuce to balance mizuna's bite. Mibuna is stronger and best used sparingly raw; it is better suited to cooking.

🍳 Cooking with Mizuna & Mibuna

Mibuna in particular is outstanding cooked: wilted briefly in a hot wok with garlic, sesame oil, and soy sauce for 60–90 seconds, it makes a superb side dish to grilled fish, chicken, or tofu. Older, larger leaves of both crops are better cooked than eaten raw. Add both to soups in the final minute of cooking. They work well in egg fried rice, noodle dishes, and as a filling for dumplings. Cooking greatly reduces the pungency, producing a mild, slightly sweet green vegetable. Do not overcook — both crops wilt to nothing in seconds.