How to Grow Imperial Lettuce
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Imperial Lettuce
Lactuca sativa var. capitata
vegetableImperial is a crisp head lettuce variety known for its dense, tightly-wrapped heads and excellent flavor. It's a heat-tolerant cultivar that produces medium to large green heads with tender interior leaves. This variety is popular in home gardens and commercial production for its reliability and storage quality.
When should you plant Imperial Lettuce in your zone?
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Example Imperial Lettuce timeline · Pittsburgh, PA (Zone 6b)
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Plant Imperial 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 Imperial Lettuce
Around Jun 21≈ 65 days after planting
Sample dates for Pittsburgh, PA. Sign up to get exact Imperial Lettuce dates for your own zip code.
Growing Conditions
Soil
Growing Zones
Find your zone →Thrives in zones 3-9; can be grown year-round in mild climates
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Get my Imperial Lettuce timeline →Growth Stages
Seedling
7-10 daysTiny cotyledons emerge, followed by true leaves. Plant is delicate and small.
Keep soil consistently moist. Provide bright light. Thin seedlings to proper spacing once first true leaves appear.
Vegetative/Leaf Development
3-4 weeksPlant establishes root system and produces multiple outer leaves. Growth is rapid during cool weather.
Maintain consistent moisture and fertilize lightly every 2-3 weeks with balanced fertilizer. Ensure adequate spacing for air circulation.
Head Formation
2-3 weeksLeaves begin to cup and overlap, forming the characteristic dense head structure. Interior leaves lighten in color.
Continue regular watering. Reduce nitrogen to encourage heading rather than excessive leaf growth. Monitor for pests.
Maturation
1-2 weeksHead becomes firm and tightly wrapped. Outer leaves are medium green; interior is pale and crispy.
Maintain consistent watering to prevent tip burn and bitterness. Do not overwater. Watch for bolting in warm weather.
Harvest Ready
Variable; harvest before temperatures exceed 75°F consistentlyHead reaches full size and optimal firmness. Leaves are crisp and sweet.
Harvest when heads feel firm but before bolting. Early morning harvest ensures crispness.
Companion Planting
Plan your garden →Plant with:
Avoid planting near:
Common Pests
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Spray with water to dislodge; use neem oil or insecticidal soap; introduce ladybugs
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and
Hand-pick at dusk; use copper tape barriers; apply diatomaceous earth; set beer traps
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Place cardboard collars around seedlings; remove debris; use Bt (Bacillus thuringiensis)
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Remove affected leaves; use row covers; spray neem oil; encourage parasitic wasps
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Ensure good air circulation; avoid overhead watering; remove infected leaves; use sulfur fungicide
Uses
Fresh Salads & Wraps
CulinaryImperial lettuce's crisp texture and mild flavor make it ideal for fresh salads, wraps, and sandwiches. The dense heads hold dressings well and provide excellent crunch. [source]
Food Service & Commercial Use
CulinaryImperial's heat tolerance and storage quality make it a preferred variety for restaurants and grocery stores, maintaining quality longer after harvest. [source]
Nutritional Benefits
MedicinalLettuce is rich in vitamins A, K, and folate, and contains compounds with potential sedative properties. It provides hydration and dietary fiber with very few calories. [source]
Garden Productivity
HouseholdImperial's reliable heading makes it an excellent choice for succession planting, allowing gardeners to enjoy continuous harvests throughout the growing season. [source]
Pollinator Support
WildlifeWhen allowed to bolt and flower, Imperial lettuce attracts bees and other beneficial insects, supporting garden biodiversity. [source]
This is not medical advice. LizPlants is not a medical resource. Always consult a qualified healthcare professional before using plants medicinally.
Harvest Tips
Harvest when heads are firm and before temperatures consistently exceed 75°F, which triggers bolting. Harvest in early morning for maximum crispness. Cut the entire head at soil level with a sharp knife, or harvest outer leaves individually for a longer harvest season. Imperial stores well in the refrigerator for 1-2 weeks when wrapped in plastic.
Fun Facts
- 🌱 Imperial lettuce was developed by the University of California and released in the 1950s, becoming one of the most widely grown head lettuce varieties worldwide.
- 🌱 Lettuce is about 95% water and was named by the Romans, who called it 'lactuca' from 'lac' (milk) because of the milky juice that flows from the stem when cut.
- 🌱 Imperial is notably heat-tolerant for a head lettuce and can be grown through warmer months with proper shade and consistent moisture, unlike many other varieties that bolt quickly in heat.
Gardening Terms
New to gardening? Learn about terms used in this guide:
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