Japanese Komatsuna, Heirloom Herb Seeds

Japanese Komatsuna, Heirloom Seeds — Japan's Superfood Green With Twice the Calcium of Whole Milk

Komatsuna (Brassica rapa var. perviridis) — Japanese Mustard Spinach — holds superfood status in its native Japan, and for good reason: it contains nearly twice as much calcium as whole milk per 100 grams, plus extraordinary levels of beta-carotene and vitamins A, C, and K. Milder than regular mustard greens, Komatsuna has a clean, versatile flavor that works beautifully raw in salads, stir-fried, pickled, or added to soups. Extremely cold hardy, it can be grown all winter long with minimal protection from hard frost. Grows well in containers. A fast, productive, and nutritionally exceptional green that deserves a place in every cool-season garden.

Why Grow Japanese Komatsuna?

• Twice the calcium of whole milk — one of the most calcium-rich vegetables you can grow
• Rich in beta-carotene and vitamins A, C, and K — genuine superfood status
• Milder than regular mustard greens — clean, versatile flavor for raw and cooked use
• Extremely cold hardy — grow all winter with minimal protection
• Container friendly — productive in pots and small spaces
• Open-pollinated heirloom — save seed year after year

Growing Notes

Direct sow outdoors 4–6 weeks before last frost or in late summer for fall/winter harvest. Sow seeds ¼ inch deep, 1–2 inches apart. Thin to 6 inches. Full sun to part shade. Water consistently. Harvest outer leaves continuously for extended production, or cut whole plant at soil level. Provide light frost protection for winter growing in zones below 5.

Days to maturity: 30–40 days
Packet size: 1.0 g / 500+ seeds
Type: Heirloom, Open-Pollinated, Annual
Spacing: 6 plants per sq ft
Sun: Full sun to part shade
USDA Zones: 3–7