How to Grow Black Seeded Simpson Lettuce
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Black Seeded Simpson Lettuce
Lactuca sativa var. crispa
vegetableBlack Seeded Simpson is a classic leaf lettuce variety prized for its tender, frilly dark green leaves and mild, delicate flavor. It forms a loose, non-heading rosette and is exceptionally easy to grow, making it ideal for beginners and succession planting. This heirloom variety is heat-tolerant compared to other lettuces and produces abundantly throughout the growing season.
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Example Black Seeded Simpson Lettuce timeline · Pittsburgh, PA (Zone 6b)
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Plant Black Seeded Simpson Lettuce
Around Apr 17Near Pittsburgh's average last spring frost.
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Tend & protect
Late spring–summerWatering, feeding, and pest-watch reminders.
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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
Soil
Growing Zones
Find your zone →Thrives in zones 3-9; grows best in cool seasons but tolerates heat better than most lettuce varieties
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Germination & Seedling
10-14 daysTiny cotyledons emerge within 7-10 days. First true leaves are small and delicate.
Keep soil moist but not soggy. Thin seedlings to proper spacing once they have 2-3 true leaves. Provide gentle light to prevent leggy growth.
Vegetative Growth
25-35 daysPlant develops multiple frilly leaves in an open rosette pattern. Leaves are tender and bright to dark green.
Water consistently. Begin light feeding with diluted liquid fertilizer every 2 weeks. Monitor for pests. Mulch around plants to retain moisture.
Full Rosette Formation
10-15 daysPlant reaches mature size with a full canopy of deeply frilled, crisp leaves. Rosette is loose and spreading.
Continue regular watering and feeding. Harvest outer leaves as needed to encourage continued growth, or wait for full head harvest.
Harvest & Bolting
Harvest window is 5-10 days; plant bolts within days afterLeaves are prime for eating. If temperatures rise or days lengthen significantly, plant sends up a central flower stalk, signaling bolting.
Harvest regularly to delay bolting. Provide afternoon shade in heat. Once bolting begins, quality declines rapidly; use remaining leaves quickly.
Companion Planting
Plan your garden →Plant with:
Avoid planting near:
Common Pests
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Spray with water to dislodge; use insecticidal soap or neem oil; encourage beneficial insects like ladybugs
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and
Remove by hand in early morning; use beer traps; apply food-grade diatomaceous earth; encourage ground beetles
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Grow resistant varieties when possible; control aphids immediately; remove infected plants; avoid touching plants when wet
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Protect seedlings with cardboard collars; maintain clean beds; handpick at night; use spinosad if severe
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Use yellow sticky traps; spray with insecticidal soap; reflective mulches deter; encourage parasitic wasps
Uses
Fresh salads and greens
CulinaryBlack Seeded Simpson's tender, delicate leaves are perfect for fresh green salads, offering a mild flavor and excellent texture. The frilly leaves add visual appeal and a pleasant crunch when harvested young. [source]
Cooking and wilting
CulinaryUnlike crisphead varieties, these tender leaves can be gently wilted in warm dishes, soups, or stir-fries, adding nutritious greens that break down easily with heat. [source]
Nutritional greens
MedicinalLettuce is rich in vitamins A, K, and folate, and provides dietary fiber and antioxidants. Regular consumption of fresh greens supports digestive health and overall wellness. [source]
Succession planting for continuous harvest
HouseholdPlant Black Seeded Simpson every 2-3 weeks for continuous supply throughout the season. Its fast maturity and forgiving nature make it perfect for beginners wanting reliable harvests. [source]
Pollinator and beneficial insect support
WildlifeWhen allowed to bolt, Black Seeded Simpson produces small yellow flowers that attract bees and other pollinators, supporting garden ecosystem 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 when they are 4-6 inches long, typically 30-40 days after sowing. Pinch or cut leaves from the outside of the rosette, leaving the center to produce new growth. For full-head harvest, cut the entire plant 1-2 inches above soil level. Harvest in early morning for peak crispness and flavor. This variety is ideal for cut-and-come-again harvesting over several weeks.
Fun Facts
- 🌱 Black Seeded Simpson is an heirloom variety that has been grown continuously since the 1850s, valued for its reliability and consistent performance across diverse growing conditions.
- 🌱 This lettuce earned its name from the dark color of its seeds, which distinguishes it from white-seeded Simpson varieties; the seed color is one of the few reliable ways to identify the variety.
- 🌱 Black Seeded Simpson is exceptionally heat-tolerant for a lettuce, able to produce leaves in temperatures up to 75°F, making it an excellent choice for spring and fall gardens in warm climates.
Gardening Terms
New to gardening? Learn about terms used in this guide:
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