Botanical Name: Daucus carota
Days to Maturity: 70–75 days
Native: Africa, Eurasia
Hardiness: Frost-tolerant biennial grown as an annual
Plant Dimensions: Roots are 8"–10" long at their peak
Variety Information: Tapered roots that are medium coral-red with an orange core. Outer color deepens to dark red after cooking. 'Atomic Red' is an imperator type carrot.
When to Sow Outside: RECOMMENDED. 2 to 4 weeks before your average last frost date, and when soil temperature is at least 45°F, ideally 60°–85°F. Successive Sowings: Every 3 weeks until 10 to 12 weeks before your average first fall frost date. In very warm climates, carrots are grown primarily in fall, winter, and spring.
When to Start Inside: Not recommended; root disturbance stunts growth.
Days to Emerge: 10–25 days
Seed Depth: ¼"
Seed Spacing: 1"
Row Spacing: 6"
Thinning: When 1" tall, thin to 1 every 3"
Harvesting: For best flavor and texture, harvest carrots any time before, and until they reach their optimal size. Peak harvest period lasts about 3 weeks, longer in the fall. Late summer-sown carrots are sweetened after having been kissed by light frost; however, harvest before soil freezes, which may destroy the crop. In USDA zone 5 or warmer, carrots can be left in the ground for storage provided they are heavily mulched; harvest as needed on days the ground is not frozen.