How to Grow True Black Tomato
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True Black Tomato
Solanum lycopersicum 'True Black'
vegetableTrue Black is a modern heirloom indeterminate tomato variety known for its deep, dark purple-black fruit with rich, complex flavor. The plants are vigorous and prolific, producing medium-sized fruits (4-6 oz) throughout the season. This variety combines excellent taste with striking appearance, making it popular among tomato enthusiasts.
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Example True Black Tomato timeline · Pittsburgh, PA (Zone 6b)
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Plant True Black 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 True Black Tomato
Around Jul 1≈ 75 days after planting
Sample dates for Pittsburgh, PA. Sign up to get exact True Black Tomato dates for your own zip code.
Growing Conditions
Soil
Growing Zones
Find your zone →Zones 5-9 are ideal; can be grown in zones 3-4 with season extension, and in zones 10+ as cool-season crop
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Seedling
3-4 weeksTiny plants with 2-4 true leaves, pale green color, developing root system
Keep soil consistently moist but not waterlogged. Provide 12-16 hours of bright light daily. Maintain 70-75°F. Thin or transplant to prevent crowding.
Vegetative
4-6 weeksRapidly growing plants developing multiple stems, leaves, and branch structure; no flowers yet
Maintain consistent moisture and full sun. Begin fertilizing with balanced fertilizer every 2 weeks. Install support stakes or cages early. Prune suckers on indeterminate types to encourage main stem growth.
Flowering
3-4 weeksYellow flowers appearing in clusters along stems; plant reaches full height and spreads
Switch to lower nitrogen, higher phosphorus fertilizer to encourage fruit set. Ensure adequate water and sunlight. Gently shake flowering clusters to aid pollination. Maintain support structures.
Fruiting & Maturation
4-6 weeksGolf ball to baseball-sized green fruits developing; gradually turning dark purple-black as they mature
Continue consistent, deep watering to prevent splitting. Reduce nitrogen fertilizer. Prune excess foliage to improve air circulation and sun penetration on fruit. Monitor for diseases. Provide support as fruit weighs down branches.
Harvest
8-12 weeks (continuous harvest until frost)Fully mature black-purple fruits that yield slightly to gentle pressure, fully colored and flavorful
Harvest when fully colored and slightly soft. Indeterminate types continue producing until frost. Allow some fruit to stay on plant for seed saving. Handle carefully to avoid bruising.
Companion Planting
Plan your garden →Plant with:
Avoid planting near:
Common Pests
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Handpick regularly; use Bt (Bacillus thuringiensis); encourage parasitic wasps; neem oil spray
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Yellow sticky traps; insecticidal soap; neem oil; reflective mulch; encourage beneficials
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Remove lower infected leaves; improve air circulation; mulch to prevent soil splash; copper fungicide; avoid overhead watering
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Remove infected foliage immediately; copper or sulfur fungicide; improve drainage; reduce humidity; plant resistant varieties
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Spray with water to dislodge; neem oil; insecticidal soap; increase humidity; encourage predatory mites
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Remove and destroy infected plants; improve soil drainage; rotate crops; use resistant varieties; sterilize tools
Uses
Fresh Eating & Salads
CulinaryTrue Black tomatoes have a complex, rich flavor with smoky, slightly sweet undertones and low acidity. Perfect for slicing into summer salads, sandwiches, or eating fresh. [source]
Sauce & Cooking
CulinaryThe deep color and concentrated flavor make True Black excellent for sauces, soups, and cooked dishes. The lower water content produces rich, flavorful reductions. [source]
Seed Saving
HouseholdTrue Black is an open-pollinated heirloom variety, making it excellent for seed saving. Gardeners can save seeds and replant them year after year, preserving this variety. [source]
Ornamental & Display
CraftThe striking dark purple-black color makes these tomatoes visually stunning for photography, display, and farmers market presentations, adding drama and uniqueness. [source]
Lycopene & Antioxidants
MedicinalDark-colored tomatoes contain high levels of lycopene and anthocyanins, which are potent antioxidants associated with various health benefits when consumed regularly. [source]
This is not medical advice. LizPlants is not a medical resource. Always consult a qualified healthcare professional before using plants medicinally.
Harvest Tips
Wait until fruits are fully black-purple and yield slightly to gentle pressure—True Black flavors best when completely ripe. Harvest in morning after dew dries. Can pick at pink stage and ripen indoors if frost threatens. Individual fruits ripen over several weeks on indeterminate plants. Handle carefully to avoid bruising. For seed saving, let 1-2 fruits fully mature and soften; extract, ferment, and dry seeds.
Fun Facts
- 🌱 True Black is not actually black but a deep purple-brown color due to high anthocyanin content, the same pigment that makes blueberries blue and eggplants purple.
- 🌱 The darker coloration develops more intensely in hot, sunny conditions, so gardeners in cooler climates may see more brown-purple fruit while those in heat-stressed areas achieve deeper black tones.
- 🌱 As an indeterminate heirloom variety, True Black will continue producing fruit prolifically until the first frost, potentially yielding 200+ fruits per plant in ideal conditions.
Gardening Terms
New to gardening? Learn about terms used in this guide:
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