How to Grow Susquehanna Tomato
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Susquehanna Tomato
Solanum lycopersicum 'Susquehanna'
vegetableSusquehanna is a reliable, disease-resistant mid-season determinate tomato variety developed by Penn State University, known for its robust productivity and excellent disease resistance to late blight and early blight. This heirloom-style variety produces medium-sized, flavorful red fruits ideal for fresh eating, sauces, and canning. It's particularly valued by gardeners in humid regions and those seeking a dependable, low-maintenance tomato.
When should you plant Susquehanna Tomato in your zone?
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Example Susquehanna Tomato timeline · Pittsburgh, PA (Zone 6b)
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Plant Susquehanna 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 Susquehanna Tomato
Around Jun 26≈ 70 days after planting
Sample dates for Pittsburgh, PA. Sign up to get exact Susquehanna Tomato dates for your own zip code.
Growing Conditions
Soil
Growing Zones
Find your zone →Thrives in zones 3-9, exceptional in zones 4-7 where disease pressure is moderate to high
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Seedling
7-10 daysTiny cotyledons emerge, followed by first true leaves; seedling is fragile with thin stem
Keep soil consistently moist but not waterlogged; provide bright light 14-16 hours daily; maintain 70°F daytime, 60°F night temperature; thin to strongest seedling if multiple sprouted
Vegetative Growth
3-4 weeks in gardenPlant develops multiple sets of true leaves, robust stem, and lateral branches; no flowers yet; plant grows rapidly
Harden off transplants before planting outdoors; pinch off lower leaves on transplants before planting to reduce disease; plant after last frost when soil is warm (60°F+); apply balanced fertilizer every 2-3 weeks
Flowering
2-3 weeksYellow flower clusters appear at leaf nodes; plant is bushy with dense foliage; flowers form in groups
Maintain consistent watering to support flower development; avoid over-nitrogen fertilization which promotes foliage over flowers; mulch around base to retain moisture and regulate temperature; install support cages or stakes early
Fruiting
3-4 weeksFlowers set fruit; small green tomatoes appear and enlarge; lower leaves may begin to yellow naturally as plant invests energy in fruit
Water deeply and consistently—irregular watering causes blossom-end rot and fruit cracking; switch to lower-nitrogen, higher-phosphorus fertilizer; remove lower leaves (12 inches from soil) as they yellow to improve air circulation; monitor for early and late blight
Harvest
4-6 weeks or until frostFruits ripen from green to red; plant typically produces 20-30+ fruits; determinate type concentrates ripening
Harvest at full color or at 'breaker stage' (first blush of color) to allow more ripening and prevent splitting; pick regularly to encourage continued production; in late season, pick green fruits before frost and ripen indoors; clean up disease-infected leaves
Companion Planting
Plan your garden →Plant with:
Avoid planting near:
Common Pests
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Remove lower leaves; ensure good air circulation; water at soil level only; apply copper fungicide or sulfur; mulch to prevent spore splash; rotate crops
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Susquehanna has good resistance; still prune lower leaves; improve air flow; avoid overhead watering; apply fungicide in humid conditions; remove infected foliage immediately
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Hand-pick caterpillars; look for dark droppings on leaves; encourage parasitic wasps; use spinosad if necessary
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Strong water spray to dislodge; yellow sticky traps; insecticidal soap; neem oil; reflective mulch
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Increase humidity and air circulation; strong water spray; neem oil; sulfur dust (not in high heat)
Uses
Sauce, Juice & Canning
CulinarySusquehanna's balanced acid-sugar ratio and determinate ripening make it excellent for tomato sauce, juice, and home canning. The firm flesh holds up well to cooking and produces smooth, flavorful products. [source]
Fresh Eating & Slicing
CulinaryMedium-sized fruits (5-8 oz) are ideal for slicing in salads, sandwiches, and fresh preparations. The flavor is balanced and reliable, with fewer mealy characteristics than some heirlooms. [source]
Nutritional & Antioxidant Benefits
MedicinalTomatoes contain lycopene, beta-carotene, and vitamin C, supporting heart health and antioxidant defense. Cooked tomatoes have higher bioavailable lycopene than raw. [source]
Disease-Resistant Gardening
HouseholdSusquehanna's proven resistance to early and late blight reduces fungicide requirements, making it ideal for organic gardening and humid climates. This makes it valuable for sustainable home food production. [source]
Pollinator Support
WildlifeTomato flowers attract bees and other pollinators, supporting garden biodiversity while improving fruit set and yield. Companion plantings of basil and flowers further enhance pollinator habitat. [source]
This is not medical advice. LizPlants is not a medical resource. Always consult a qualified healthcare professional before using plants medicinally.
Harvest Tips
Susquehanna is determinate, meaning most fruit ripens within 2-3 weeks, ideal for canning. Harvest when fully red and slightly soft; twist gently or clip with pruners. Pick at breaker stage in hot weather to prevent splitting. In fall, pick green tomatoes before frost (ripens in 20-30 days indoors at 68-72°F). Regular harvesting encourages more fruit set.
Fun Facts
- 🌱 Susquehanna was developed at Penn State University and released in 1965, bred specifically for disease resistance in eastern United States humid conditions where blight is a major problem.
- 🌱 The variety is named after the Susquehanna River, which flows through Pennsylvania and Maryland—regions where late blight devastates tomato crops and made this variety's resistance invaluable.
- 🌱 Susquehanna is determinate, meaning it grows to a fixed height (3-4 feet) and concentrates fruit ripening, making it perfect for gardeners who want a quick, concentrated harvest for canning in one or two weeks rather than continuous small harvests.
Gardening Terms
New to gardening? Learn about terms used in this guide:
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