How to Grow Marathon

Wikimedia Commons

Marathon

Lactuca sativa var. longifolia

vegetable

Marathon is a romaine/cos lettuce variety known for its elongated, upright head and crisp, tender leaves. It produces well-structured heads with excellent flavor and texture, making it popular for fresh salads and culinary use. This variety is prized for its disease resistance and reliable performance in various growing conditions.

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Example Marathon timeline · Pittsburgh, PA (Zone 6b)

Plant Marathon
Around Apr 17

Near Pittsburgh's average last spring frost.
Tend & protect
Late spring–summer

Watering, feeding, and pest-watch reminders.
Harvest Marathon
Around Jun 11

≈ 55 days after planting

Sample dates for Pittsburgh, PA. Sign up to get exact Marathon dates for your own zip code.

Growing Conditions

☀️

Sun: Full sun to partial shade; 6+ hours of direct sunlight daily for best results, partial shade beneficial in hot climates

💧

Water: Keep soil consistently moist but not waterlogged; water deeply 1-2 inches per week, more frequently in hot weather; maintain even moisture to prevent bolting and bitterness

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Spacing: 8-12 inches

📅

Days to maturity: 55-70

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Planting depth: 0.25-0.5 inches

Soil

Type: Well-draining loamy soil rich in organic matter

pH: 6.0-7.0

Amendments:

Compost well-rotted manure peat moss balanced slow-release fertilizer

Growing Zones

Find your zone →

Thrives in zones 3-9; can grow year-round in zones 9-10 with proper timing

2a 2b 3a 3b 4a 4b 5a 5b 6a 6b 7a 7b 8a 8b 9a 9b 10a

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Growth Stages

Germination & Seedling

2-3 weeks

Seeds sprout in 7-10 days at 60-70°F; cotyledons emerge followed by first true leaves

Keep soil moist but not soggy; maintain cool temperatures; provide bright light to prevent leggy seedlings; thin seedlings to proper spacing once they have 2-3 true leaves

Vegetative Growth

3-4 weeks

Plant develops multiple leaves in a rosette pattern; gradual formation of the characteristic elongated head structure begins

Maintain consistent watering; provide full sun or light afternoon shade in hot climates; fertilize every 2-3 weeks with balanced fertilizer; mulch to conserve moisture and keep soil cool

Head Formation

2-3 weeks

Leaves compact and form a tight, upright head; internal leaves lighten in color; head becomes more dense and structured

Continue regular watering with consistent moisture; avoid overhead watering to prevent fungal issues; monitor for pests and diseases; ensure adequate spacing for air circulation

Maturity & Harvest-Ready

1-2 weeks

Head reaches full size (typically 8-10 inches tall), feels firm and compact when gently squeezed; outer leaves are green, inner leaves are pale green to light yellow

Harvest when head feels firm but before bolting; cool temperatures prolong harvest window; harvest in early morning for crispest leaves; continue watering even at harvest stage

Post-Harvest / Regrowth

1-3 weeks

After cutting outer leaves or harvesting the whole head, plant may regrow secondary leaves if left in ground in cool conditions

If harvesting outer leaves only, continue watering and care for successive harvests; if cutting whole head, leave roots in place for possible regrowth in cool seasons

Companion Planting

Plan your garden →

Plant with:

Radish Carrot Beet Onion Garlic Chamomile Dill Borage Nasturtium Marigold

Avoid planting near:

Celery Parsnip Cabbage Cauliflower Broccoli

Common Pests

Spray with insecticidal soap or neem oil; encourage beneficial insects; use reflective mulches; strong water spray to dislodge
and (Limax and Helix spp.)
Hand-pick in early morning or evening; use beer traps; copper barriers; diatomaceous earth; encourage ground beetles and birds
Plant disease-resistant varieties; control aphid vectors; remove and destroy infected plants; avoid handling plants when they're wet
Improve air circulation; avoid overhead watering; remove affected leaves; use sulfur fungicide if severe; plant resistant varieties
Spray with neem oil or insecticidal soap; use yellow sticky traps; encourage parasitic wasps; increase air flow

Uses

🍳

Salads & Fresh Eating

Culinary

Marathon's crisp, tender leaves are ideal for fresh green salads, Caesar salads, and vegetable platters. The elongated leaves hold dressings well and provide excellent crunch and mild, slightly sweet flavor. [source]

🍳

Wraps & Lettuce Cups

Culinary

The sturdy leaves of Marathon are perfect for lettuce wraps, lettuce cups, and as a low-carb substitute for bread or tortillas in various cuisines. [source]

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Home Kitchen Garden Staple

Household

Marathon is one of the easiest and most productive lettuces for home gardeners, offering reliable yields and extended harvest seasons in cool weather. [source]

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Nutritional & Wellness Benefits

Medicinal

Rich in vitamins A, C, and K, as well as folate and minerals; low in calories and supports digestive health. Lettuce has been used traditionally to promote relaxation and sleep. [source]

🦋

Pollinator & Beneficial Insect Support

Wildlife

When left to bolt and flower, Marathon produces small yellow flowers that attract pollinators and beneficial insects to the garden ecosystem. [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 the head is firm and compact, typically 55-70 days from planting. Cut the entire head at the base with a sharp knife in early morning when leaves are crispest and most hydrated. For continuous harvest, pick outer leaves once the plant is established, leaving the inner head to continue growing. Avoid harvesting during extreme heat to prevent bitterness. Store in refrigerator in a plastic bag for up to 2 weeks.

Fun Facts

🌱 Marathon is a reliable heirloom variety that has been cultivated for centuries; romaine lettuce itself was named after the Romaine region near Rome, Italy, where it was widely cultivated.
🌱 Unlike iceberg lettuce, romaine varieties like Marathon contain significantly more nutrients and antioxidants, making them a nutritional powerhouse for fresh eating.
🌱 Lettuce seed remains viable for 4-6 years when stored properly in cool, dry conditions, making it economical for home gardeners to save seed from their best plants.

Gardening Terms

New to gardening? Learn about terms used in this guide:

Bolt Full Sun Mulch Partial Shade True Leaves

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