How to Grow Knee Hi Tomato
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Knee Hi Tomato
Solanum lycopersicum 'Knee Hi'
vegetableKnee Hi is a determinate dwarf tomato variety that grows 2-3 feet tall, making it ideal for containers and small spaces. It produces full-sized, flavorful red tomatoes despite its compact growth habit. This variety was developed by Cornell University and is known for its productivity and disease resistance.
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Example Knee Hi Tomato timeline · Pittsburgh, PA (Zone 6b)
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Plant Knee Hi 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 Knee Hi Tomato
Around Jun 16≈ 60 days after planting
Sample dates for Pittsburgh, PA. Sign up to get exact Knee Hi Tomato dates for your own zip code.
Growing Conditions
Soil
Growing Zones
Find your zone →Thrives in zones 3-10; can be grown as annual in all zones
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Seedling
7-14 daysTiny plants with cotyledons (seed leaves) emerge, followed by first true leaves
Keep soil consistently moist but not waterlogged; provide bright light 14-16 hours daily; maintain 65-75°F; thin to strongest seedlings
Vegetative Growth
3-4 weeks (as seedling); 2-3 weeks after transplanting outdoors before floweringPlant develops sturdy stem and multiple sets of true leaves; compact, bushy growth habit becomes apparent
Harden off transplants gradually before outdoor planting; maintain consistent moisture; fertilize weekly with balanced fertilizer; pinch suckers lightly if needed to maintain shape
Flowering
2-4 weeksYellow flowers appear in clusters along the stem; plant reaches maximum compact height (2-3 feet)
Continue consistent watering; switch to lower nitrogen fertilizer (higher phosphorus/potassium); ensure adequate sunlight for fruit set; support plant with small cage or stake
Fruiting
2-3 weeksSmall green fruits develop at flower sites; fruits swell and begin color change from green to light pink to red
Maintain steady watering to prevent cracking; remove lower leaves for air circulation once fruit is established; apply mulch to retain moisture; stake or cage for support
Harvest & Maturity
3-6 weeks (until first frost)Fruits reach full red color and slight softness when gently squeezed; plant continues producing until frost
Harvest ripe fruits regularly to encourage continued production; reduce watering slightly as season progresses; remove damaged or diseased fruit; expect 30-50+ fruits per plant
Companion Planting
Plan your garden →Plant with:
Avoid planting near:
Common Pests
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Hand-pick; encourage beneficial parasitic wasps; use Bt (Bacillus thuringiensis) if infestations are severe
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Strong water spray to dislodge; yellow sticky traps; neem oil spray; reflective mulch deterrent
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Spray with strong water; insecticidal soap; neem oil; encourage ladybugs and lacewings
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Increase humidity; strong water spray; neem oil; miticide if severe
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Remove lower infected leaves; improve air circulation; avoid overhead watering; apply copper fungicide; mulch to prevent soil splash
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Ensure good air circulation; apply sulfur or copper fungicide; remove infected leaves; avoid overhead watering
Uses
Fresh eating and salads
CulinaryKnee Hi produces full-sized, flavorful red tomatoes perfect for slicing into salads, sandwiches, or eating fresh off the vine. The compact plant makes it ideal for gardeners with limited space who still want abundant fresh tomatoes. [source]
Sauces and cooking
CulinaryThe productive nature of Knee Hi makes it excellent for preservation; the fruits can be used for canning, sauce-making, or roasting throughout the season. [source]
Container gardening
HouseholdKnee Hi's dwarf determinate habit makes it perfect for growing in 5-gallon containers on patios, balconies, or small urban gardens where space is limited. [source]
Nutritional benefits
MedicinalRed tomatoes are rich in lycopene, vitamin C, potassium, and other antioxidants that support heart health and immune function. [source]
Pollinator attraction
WildlifeTomato flowers attract bees and other pollinators to the garden, supporting biodiversity and improving overall garden ecosystem health. [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 but still slightly firm; harvest in morning after dew dries for best flavor; twist gently or cut with shears; can pick at pink stage and ripen indoors if frost threatens; regular harvesting encourages more production; expect first ripe fruit 60-75 days from transplanting
Fun Facts
- 🌱 Knee Hi was developed by Cornell University specifically for small-space gardeners and container growing, representing one of the earliest compact determinate tomato varieties bred for urban and patio cultivation.
- 🌱 Despite reaching only 2-3 feet tall, a single healthy Knee Hi plant can produce 30-50+ full-sized tomatoes in a season, making it one of the most productive compact varieties per square foot.
- 🌱 The variety is disease-resistant and was bred for disease tolerance, making it a popular choice for organic gardeners and those dealing with common tomato diseases in humid climates.
Gardening Terms
New to gardening? Learn about terms used in this guide:
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