How to Grow Benjamin Franklin

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Benjamin Franklin

Solanum lycopersicum 'Benjamin Franklin'

vegetable

Benjamin Franklin is a heirloom indeterminate tomato variety known for its large, flavorful red fruits and exceptional disease resistance. This prolific producer yields abundant medium-to-large tomatoes throughout the season and was developed by Cornell University for superior flavor and resilience. It's prized by home gardeners for both taste and reliable performance in challenging growing conditions.

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Example Benjamin Franklin timeline · Pittsburgh, PA (Zone 6b)

  1. Plant Benjamin Franklin

    Around Apr 17

    Near Pittsburgh's average last spring frost.

  2. Tend & protect

    Late spring–summer

    Watering, feeding, and pest-watch reminders.

  3. Harvest Benjamin Franklin

    Around Jun 26

    ≈ 70 days after planting

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

Growing Conditions

☀️
Sun: Full sun, 6-8 hours daily minimum
💧
Water: Consistent moisture; water deeply 1-2 inches per week, more in hot weather. Keep foliage dry to prevent disease. Water at soil level.
📏
Spacing: 24 inches
📅
Days to maturity: 70-85 days from transplant
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Planting depth: Plant seed ¼ inch deep; transplant buried up to first true leaves

Soil

Type: Well-draining loamy soil rich in organic matter
pH: 6.0-6.8
Amendments:
compost aged manure perlite balanced fertilizer (5-10-10)

Growing Zones

Find your zone →

Thrives in zones 5-9; can be grown in zones 3-4 with season extension

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

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Growth Stages

1

Seedling

2-3 weeks

Tiny green shoots emerge with two cotyledons; first true leaves appear within 7-10 days

Provide bright light 14-16 hours daily; maintain warmth (70-75°F); keep soil moist but not waterlogged

2

Vegetative Growth

4-6 weeks

Plant develops multiple sets of true leaves and a stronger stem; reaches 6-12 inches tall indoors

Thin to strongest seedling; provide gentle air circulation; begin hardening off 1-2 weeks before transplanting

3

Flowering

3-4 weeks after transplanting outdoors

First flower clusters appear; small yellow flowers form along the main stem and side shoots

Provide full sun outdoors; ensure consistent watering and mulch; prune lower leaves once fruit sets; stake or cage for support

4

Fruiting

4-6 weeks

Green marble-sized fruits develop rapidly; begin turning red within 20-30 days; multiple trusses bear fruit simultaneously

Water consistently; apply balanced or slightly lower nitrogen fertilizer; remove diseased leaves; maintain strong stakes/cages

5

Harvest & Mature

Until first frost (8-12 weeks)

Fruits reach full size (6-8 oz) and deep red color; plant continues producing until frost

Pick fruit at full color or slight blush for best flavor; continue watering and feeding; prune suckers to encourage fruit ripening

Companion Planting

Plan your garden →

Plant with:

Avoid planting near:

brassicas (cabbage, broccoli) fennel dill potato

Common Pests

  • Hand-pick; encourage parasitic wasps; use Bt (Bacillus thuringiensis); neem oil spray

  • Yellow sticky traps; strong water spray; insecticidal soap; reflective mulch

  • Remove lower leaves; improve air circulation; mulch; avoid overhead watering; copper fungicide

  • Remove infected foliage; maintain spacing; copper-based fungicide; avoid wet foliage at night

  • Increase humidity; neem oil; insecticidal soap; strong water spray

Uses

🍳

Fresh Eating & Slicing

Culinary

Benjamin Franklin tomatoes are exceptional for fresh eating with a perfect balance of sweetness, acidity, and complex flavor. Their large size and meaty texture make them ideal for slicing into salads, sandwiches, and heirloom tomato platters. [source]

🍳

Sauce & Preservation

Culinary

The high pectin and acid content makes these tomatoes excellent for making sauce, paste, and canning. Their robust flavor concentrates beautifully when cooked down for marinara or salsa. [source]

💊

Antioxidant Source

Medicinal

Tomatoes are rich in lycopene, a powerful antioxidant linked to cardiovascular and prostate health. Benjamin Franklin tomatoes, like other red varieties, provide high levels of this beneficial compound. [source]

🏠

Disease Resistance

Household

Bred at Cornell University, this variety was developed specifically for resistance to early blight and late blight, making it an excellent choice for organic gardeners and those in humid climates. [source]

🦋

Pollinator Attraction

Wildlife

The abundant flowers attract bees and other pollinators, supporting garden biodiversity and ecosystem health while ensuring excellent fruit set. [source]

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

Harvest Tips

Pick tomatoes when fully red and slightly soft to pressure—this variety ripens fully on the vine for best flavor. Twist gently or cut with shears. Harvest regularly to encourage continued production. In late season, pick mature green tomatoes before first frost and ripen indoors at room temperature.

Fun Facts

  • 🌱 Benjamin Franklin was developed by Cornell University specifically to resist both early and late blight, making it one of the most disease-resistant heirloom tomato varieties available to home gardeners.
  • 🌱 This indeterminate variety can grow 6-8 feet tall and produce dozens of large tomatoes throughout the season, often outperforming modern hybrids in taste and reliability.
  • 🌱 The variety was named after Benjamin Franklin, one of America's founding fathers and a prolific botanist and inventor who spent time in France studying agriculture and gardening practices.

Gardening Terms

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

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