How to Grow Double Decker Tomato
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Double Decker Tomato
Solanum lycopersicum 'Double Decker'
vegetableDouble Decker is an heirloom tomato variety known for its distinctive two-chambered fruit structure, where one lobe sits atop another, creating a stacked appearance. The fruits are medium-sized, typically weighing 6-8 ounces, with a rich, complex flavor and relatively meaty interior with few seeds. This determinate variety produces heavily and is prized by heirloom tomato enthusiasts for both its unique look and excellent taste.
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Example Double Decker Tomato timeline · Pittsburgh, PA (Zone 6b)
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Plant Double Decker Tomato
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 Double Decker Tomato
Around Jun 26≈ 70 days after planting
Sample dates for Pittsburgh, PA. Sign up to get exact Double Decker Tomato dates for your own zip code.
Growing Conditions
Soil
Growing Zones
Find your zone →Thrives in zones 5-9; can grow in zones 3-4 with season extension and protection
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Seedling (Weeks 1-3)
3 weeksTiny plants with cotyledons followed by true leaves. Very delicate with thin stems.
Keep soil consistently moist but not waterlogged. Provide bright light 14-16 hours daily under grow lights. Maintain 65-75°F temperature. Begin very light fertilization at true leaf stage.
Vegetative Growth (Weeks 3-6 indoors, or until transplant)
3-4 weeksStocky growth with multiple true leaves, developing a stronger root system. Plant gains height and leaf mass.
Thin to strongest seedlings. Pot up to larger containers as needed. Maintain bright light. Fertilize every 1-2 weeks with balanced, diluted fertilizer. Harden off outdoors 1-2 weeks before transplanting.
Establishment & Flowering (Weeks 1-4 after transplant)
3-4 weeksPlant recovers from transplant shock, establishes in ground, grows taller with more branches. First flower clusters appear.
Mulch around base with 2-3 inches (avoid touching stem). Install sturdy stakes/cages early. Remove lower leaves if they touch soil. Water consistently. Begin moderate fertilization; reduce nitrogen once flowering starts.
Fruit Set & Development (Weeks 4-8 after transplant)
4-5 weeksFlowers set fruit; small green fruits develop into marble-sized, then walnut-sized tomatoes. Plant fills out with abundant foliage.
Maintain consistent watering to prevent splitting and blossom end rot. Prune lower leaves as plant grows. Remove suckers on indeterminate varieties if staked. Monitor for pests and disease. Support heavy fruit clusters with twine or clips.
Ripening & Harvest (Weeks 8-12+ after transplant)
4+ weeks until frostFruits mature from green to light pink to full red/orange. Plant may show stress as it focuses energy on fruit ripening.
Continue consistent watering. Stop fertilizing or use low-nitrogen formula to focus energy on fruit. Harvest ripe fruit regularly to encourage continued production. Remove diseased leaves promptly. In late season, prune excessive foliage to direct energy to remaining fruit.
Companion Planting
Plan your garden →Plant with:
Avoid planting near:
Common Pests
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Hand-pick large caterpillars in early morning/late evening. Use Bt (Bacillus thuringiensis) spray. Encourage parasitic wasps. Remove egg clusters from leaf undersides.
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Spray with insecticidal soap or neem oil weekly. Use yellow sticky traps. Remove heavily infested leaves. Increase air circulation with fans.
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Mist plants to increase humidity. Spray with water to dislodge mites. Use neem oil or sulfur spray. Remove heavily infested leaves.
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Remove lower infected leaves. Improve air circulation. Mulch to prevent soil splash. Spray with copper fungicide or sulfur. Water at soil level only.
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Remove infected foliage immediately. Ensure good air circulation. Spray with copper fungicide. Avoid overhead watering. Destroy infected plants completely.
Uses
Fresh slicing and sandwich tomato
CulinaryDouble Decker's meaty texture, few seeds, and excellent flavor make it ideal for fresh slicing. The unique shape makes attractive presentation on plates and sandwiches. [source]
Sauce and paste making
CulinaryThe low seed content and dense flesh of Double Decker make it suitable for tomato sauces, pastes, and cooking applications where water content matters. [source]
Ornamental and novelty gardening
HouseholdThe distinctive two-chambered appearance makes Double Decker a conversation piece and educational plant for gardeners interested in heirloom varieties and unusual plant traits. [source]
Canning and preservation
CulinaryWhile not a paste tomato, Double Decker can be canned whole, halved, or made into salsa or other preserved products due to its firm texture. [source]
Garden pollinator support
WildlifeTomato flowers attract bees and other pollinators, supporting garden biodiversity and ensuring good fruit set for maximum harvest. [source]
Harvest Tips
Harvest when fruit is fully colored (deep red for this variety) and yields slightly to gentle pressure. Pick in morning when cool. Double Decker can be harvested at 'breaker stage' (color just beginning to show) and ripened indoors. Twist gently or cut with pruners. Continue harvesting throughout season to encourage more flowering. After first frost, pick all remaining fruit (including green ones) and ripen indoors at 68-72°F.
Fun Facts
- 🌱 Double Decker gets its name from its distinctive two-chambered fruit structure, where one lobe sits stacked atop the other, creating an unusual appearance that makes it instantly recognizable among tomato varieties.
- 🌱 This heirloom variety became popular among gardeners and farmers who prized unusual and characterful tomatoes, and it remains a favorite in heirloom seed exchanges despite being less commercially available than modern hybrids.
- 🌱 The unusual shape of Double Decker tomatoes makes them excellent for educational purposes in schools, as children find the stacked-fruit structure fascinating and it encourages interest in growing food plants.
Gardening Terms
New to gardening? Learn about terms used in this guide:
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