Botanical Name: Brassica rapa subsp. nipposinica
Days to Maturity: 30–60 days
Native: Probably Eurasia
Hardiness: Frost-tolerant annual
Plant Dimensions: 24" tall, and 16"–24" wide
Variety Information: Smooth dark green, glossy leaves with thin, lighter green midribs and milder flavor than true mustards. Flowers, stalks, and buds are also edible. Slow to bolt and heat and cold tolerant.
Attributes: Good for Containers, Heat Tolerant
When to Sow Outside: RECOMMENDED. 4 to 6 weeks before your average last frost date, when soil temperature is at least 40°F, ideally 60°–75°F. Successive Sowings: Every 3 weeks until 10 to 12 weeks before your average first fall frost date for continuous harvest. Mild Climates: Sow in late fall through winter for cool–season harvest.
When to Start Inside: Not recommended; transplant stress can cause plants to bolt (prematurely flower).
Days to Emerge: 5–10 days
Seed Depth: ¼"
Seed Spacing: A group of 3 seeds every 4" – 6"
Row Spacing: 12"–18"
Thinning: When 3" tall, thin to 1 every 4" – 6"
Harvesting: Harvest in the morning if possible. You may start harvesting leaves when they are 2" tall, as needed; remove no more than 1/3 of the plant if regrowth is desired, or let plant grow to maturity and harvest entire plant. Late summer crops will last until the first hard freeze.