How to Grow Black Seeded Simpson Lettuce

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Black Seeded Simpson Lettuce

Lactuca sativa var. crispa

vegetable

Black Seeded Simpson is a classic loose-leaf lettuce variety prized for its tender, frilly leaves and mild flavor. It forms no head, instead producing a loose rosette of deeply lobed, crinkled leaves that range from light to medium green. This cold-hardy variety is prolific, fast-growing, and excellent for successive plantings throughout the growing season.

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Example Black Seeded Simpson Lettuce timeline · Pittsburgh, PA (Zone 6b)

  1. Plant Black Seeded Simpson Lettuce

    Around Apr 17

    Near Pittsburgh's average last spring frost.

  2. Tend & protect

    Late spring–summer

    Watering, feeding, and pest-watch reminders.

  3. Harvest Black Seeded Simpson Lettuce

    Around Jun 1

    ≈ 45 days after planting

Sample dates for Pittsburgh, PA. Sign up to get exact Black Seeded Simpson Lettuce dates for your own zip code.

Growing Conditions

☀️
Sun: Full sun to partial shade; 4-6 hours of sunlight daily optimal, afternoon shade in hot climates prevents bolting
💧
Water: Keep soil consistently moist but not waterlogged; 1-1.5 inches per week; more frequent shallow watering in hot weather; morning watering reduces disease
📏
Spacing: 6 inches
📅
Days to maturity: 45-60 days from seed to harvest-ready leaves; 30-40 days for baby greens
🌱
Planting depth: 0.25

Soil

Type: Rich, well-draining loamy soil with high organic matter
pH: 6.0-7.0
Amendments:
Compost Aged manure Peat moss or coco coir Balanced organic fertilizer

Growing Zones

Find your zone →

Zones 3-9; thrives in cool seasons and tolerates light frosts

2a 2b 3a 3b 4a 4b 5a 5b 6a 6b 7a 7b 8a 8b 9a 9b

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Growth Stages

1

Germination

5-10 days

Seeds sprout and develop cotyledons (seed leaves); seedlings are delicate and small

Keep soil moist and cool (60-70°F); provide light once sprouts emerge; thin seedlings to prevent damping off

2

Seedling & Early Growth

10-14 days

True leaves emerge and seedling develops 2-4 leaves; plant is still small and tender

Continue consistent moisture; avoid overhead watering to prevent fungal disease; provide bright light; no fertilizer needed yet if soil is rich

3

Vegetative & Leaf Development

20-30 days

Plant rapidly produces more deeply lobed, frilly leaves; forms loose rosette; leaves become tender and harvestable

Water regularly; side-dress with compost or balanced fertilizer every 2-3 weeks; thin crowded plants; watch for bolting signs in heat

4

Harvest-Ready Maturity

Variable; can produce for 4-6 weeks with proper care and cool weather

Rosette reaches full size with abundant crinkled leaves; plant is lush and tender; may begin to bolt in heat

Begin harvesting outer leaves; maintain moisture and cool conditions; harvest before flowering to ensure best flavor and texture

5

Bolting & Senescence

1-2 weeks before unsuitable for harvest

Plant sends up flower stem; leaves become bitter and tough; plant diverts energy to seed production

Harvest remaining leaves immediately if not yet done; compost plant; plant new crop in cooler season if desired

Companion Planting

Plan your garden →

Plant with:

Avoid planting near:

Cabbage Celery Parsnip Fennel

Common Pests

  • Spray with water to dislodge; use insecticidal soap; encourage beneficial insects like ladybugs; neem oil as last resort

  • and

    Remove by hand (especially at night); use beer traps; copper tape around beds; diatomaceous earth; encourage ground beetles

  • Control aphid vectors; remove affected plants; plant resistant varieties; control weeds that harbor virus

  • Improve air circulation; avoid overhead watering; remove infected leaves; choose resistant varieties; sulfur-based fungicides

  • Remove heavily affected leaves; use row covers; neem oil; encourage parasitic wasps

Uses

🍳

Salads & Fresh Greens

Culinary

Black Seeded Simpson's tender, frilly leaves are excellent raw in mixed green salads, providing mild flavor and delicate texture. The leaves can be harvested continuously for fresh eating throughout the season. [source]

🍳

Cooking & Sautéing

Culinary

The leaves can be lightly cooked in soups, stews, or stir-fries, maintaining their tender texture better than some other varieties. Wilts quickly, making it useful in quick-cooked dishes. [source]

🍳

Sandwich & Wrap Ingredient

Culinary

The pliable, ruffled leaves make excellent wraps and sandwich layers, adding crisp texture and mild flavor to composed dishes. [source]

🏠

Microgreens Production

Household

Black Seeded Simpson seeds are commonly used to grow nutrient-dense microgreens indoors, ready to harvest in 10-14 days for use on salads, sandwiches, and garnishes. [source]

💊

Nutritional & Wellness Support

Medicinal

Like all lettuce, Black Seeded Simpson is low in calories and contains vitamins A, K, and folate, plus fiber and various phytonutrients supporting digestive and bone health. [source]

This is not medical advice. LizPlants is not a medical resource. Always consult a qualified healthcare professional before using plants medicinally.

Harvest Tips

Begin harvesting outer leaves once plant is 6-8 inches tall (about 30-35 days); pick outer leaves regularly to encourage continued production; harvest in early morning when leaves are crisp and hydrated; cut or pinch leaves at base; can harvest entire plant at once by cutting 1 inch above soil, allowing regrowth; most tender in cool, moist conditions; harvest before bolting (flower stalk emergence) for best flavor

Fun Facts

  • 🌱 Black Seeded Simpson has been grown since at least the 1800s and remains a beloved heirloom variety; the name refers to the dark color of its seeds rather than the plant itself
  • 🌱 This variety is an 'open-pollinated' or heirloom lettuce, meaning you can save seeds from mature plants to grow next season's crop
  • 🌱 Black Seeded Simpson is notably bolting-resistant compared to some other loose-leaf varieties, making it excellent for spring and fall crops in most climates

Gardening Terms

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