Botanical Name: Spinacea oleracea (hybrid)
Days to Maturity: 20–25 days
Native: Southwest Asia
Hardiness: Frost-tolerant annual. Very cold hardy; fall-sown plants may overwinter even in climates with sub-zero temperatures.
Variety Information: As a baby green, small, dark green and smooth, tender leaves.
When to Sow Outside: 4 to 6 weeks before your average last frost date, when soil temperature is above 40°F, ideally 50°–75°F. Successive Sowings: Every 3 weeks until 4 weeks before your average first fall frost date. Soil temperatures above 85°F half germination.
When to Start Inside: RECOMMENDED. Sow indoors any time of year, with indoor temperatures 60°–75°F. Successive Sowings: Every 2 weeks for a continual supply.
Days to Emerge: 5–10 days
Seed Depth: ½"
Seed Spacing: ¾"
Thinning: Not required.
Harvesting: When seedlings emerge, the first pair of leaves to show are the cotyledons, which can look very different from the leaves that follow, called "true" leaves. Spinach baby greens are ready to harvest 20 to 25 days after sowing, when they have true leaves, at 2"–4". Slow growers, or cool growing temperatures may require more time. Harvest by cutting just above the soil line. For more than one harvest (up to 3 before flavor declines) leave about 1/2" of leafy growth on the small plants so they can regenerate.