Osaka Shirona Chinese Cabbage Seeds (Brassica rapa var. pekinensis) – Japanese Loose-Leaf Napa Cabbage, Heat & Cold Tolerant, Fast-Growing Mild Green for Microgreens to Full Harvest

Minimum: 50+ Seeds

Osaka Shirona Chinese Cabbage — The Japanese Loose-Leaf That Works in Any Season

Osaka Shirona is the rare brassica that tolerates both cold and heat. This loose-head variety produces abundant bright green leaves with wide, firm white stems and genuinely handles temperature swings that would make other greens panic. Start harvesting as microgreens in 10-14 days, baby leaves in 20-30 days, or full maturity in 40-60 days. The plant is mild-tasting, vitamin A-rich, and equally at home raw in salads, stir-fried with garlic, or traditionally dried and pickled for winter. The loose structure is more attractive than tight heads, and every leaf is harvestable without waiting for a head to form. In frost-free areas, Osaka Shirona can be sown year-round, making it the utility player of Asian greens.

Who Grows Osaka Shirona Chinese Cabbage?

Japanese and Asian cooks wanting authentic greens for stir-fries and soups. Gardeners in variable climates wanting a brassica that handles temperature swings. Microgreens producers seeking fast germination and attractive yields. Anyone with a long growing season wanting continuous harvest from spring through fall. And anyone who appreciates a plant that adapts rather than complains.

What This Plant Actually Is

Brassica rapa var. pekinensis 'Osaka Shirona', a loose-head variety possibly descended from Chinese cabbage and pak choi. Plants produce abundant medium-sized bright green leaves with wide, firm white petioles. The flavor is distinctly mild. Leaves are packed with vitamin A. The variety tolerates both cold and heat... unusual in the cabbage family—making it suitable for spring, summer, fall, and year-round growing in frost-free areas. Maturity is flexible: microgreens 10-14 days, baby leaves 20-30 days, full harvest 40-60 days. Continuous leaf harvest without waiting for a head. Heirloom, open-pollinated.

In the Kitchen

• Microgreens: Harvest at 10-14 days for peppery sprouts with mild brassica flavor.
• Baby Leaves: At 20-30 days, tender and sweet. Perfect for fresh salads or Asian slaw.
• Stir-Fries: Chop and cook quickly with garlic, sesame oil, ginger. Stems stay pleasantly firm.
• Soups: Add leaves to broths. Mild flavor complements rather than dominates.
• Traditional Preservation: Dry leaves for winter storage or pickle for shelf life.
• Raw Salads: Mature leaves still mild and tender.

Growing Osaka Shirona Chinese Cabbage

• Sowing: Direct sow or start indoors. ¼ inch deep in moist soil. Year-round in frost-free areas.
• Germination: 5-10 days at 65-70°F.
• Spacing: 3-4 inches for microgreens/baby leaf. 8-12 inches for full plants.
• Sunlight: Full sun to part shade. 5-6 hours direct light daily.
• Soil: Fertile, well-drained with organic matter. pH 6.0-7.5.
• Water: Keep consistently moist. Never let dry out.
• Temperature: Prefers 50-70°F. Tolerates both cold and heat but avoid peak summer.
• Fertilizer: Light feeding. Side-dress every 3-4 weeks.
• Harvest Microgreens: Cut at soil level at 10-14 days.
• Harvest Baby Leaf: Pick outer leaves at 20-30 days; plant continues.
• Harvest Full: Cut at base or pull at 40-60 days.

Before You Close This Page

Japanese heirloom loose-leaf. 40-60 days to maturity. Microgreens in 10-14 days, baby leaf in 20-30. Bright green leaves, firm white stems. Mild flavor. Cold and heat tolerant. Vitamin A-rich. Continuously harvestable without forming heads. Perfect for microgreens, salads, stir-fries, soups, preservation. Fast-growing, adaptable. One planting, endless harvests.