How to Grow Full Black Tomato

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Full Black Tomato

Solanum lycopersicum 'Full Black'

vegetable

Full Black is a striking heirloom indeterminate tomato variety featuring deep purple-black fruits with rich, complex flavors. The plants are vigorous growers that produce medium to large-sized beefsteak tomatoes throughout the season. Known for their dark coloring and excellent taste, they're a favorite among tomato enthusiasts.

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Example Full Black Tomato timeline · Pittsburgh, PA (Zone 6b)

  1. Plant Full Black Tomato

    Around Apr 17

    Near Pittsburgh's average last spring frost.

  2. Tend & protect

    Late spring–summer

    Watering, feeding, and pest-watch reminders.

  3. Harvest Full Black Tomato

    Around Jul 1

    ≈ 75 days after planting

Sample dates for Pittsburgh, PA. Sign up to get exact Full Black Tomato dates for your own zip code.

Growing Conditions

☀️
Sun: Full sun, 8+ hours daily (more is better for dark fruit coloration)
💧
Water: Consistent watering of 1-2 inches per week; keep soil evenly moist but not waterlogged. Water at the base to avoid fungal disease. Drought stress can intensify the dark coloration but reduce yields.
📏
Spacing: 24 inches
📅
Days to maturity: 75-85 days from transplant
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Planting depth: 0.25 inches for seeds; plant transplants deeper (up to first true leaves)

Soil

Type: Well-draining loamy soil rich in organic matter
pH: 6.0-6.8
Amendments:
Compost Aged manure Peat moss or coconut coir Balanced fertilizer (5-5-5 or similar) Calcium (crushed eggshells or gypsum to prevent blossom end rot)

Growing Zones

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Thrives in zones 5-9, can be grown in 3-4 with protection

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 sprouts emerge with cotyledons (seed leaves), followed by true leaves. Plants are delicate and light green.

Provide bright light (14-16 hours) under grow lights or on sunny windowsill. Keep soil consistently moist but not soggy. Maintain warmth (70-75°F). Thin seedlings to strongest one per cell.

2

Vegetative Growth

3-4 weeks indoors, 1-2 weeks hardening off

Young transplants develop 4-6 sets of true leaves and establish strong root systems. Leaves are deep green and stems thicken.

Harden off seedlings before transplanting outdoors over 7-10 days. Transplant when 6-8 inches tall and have 4-6 true leaves. Plant deep, burying stem up to first leaves to strengthen root system. Prune lower leaves after transplanting if desired to reduce disease.

3

Flowering

4-6 weeks until first fruit set

Indeterminate plants grow continuously, producing yellow flowers in clusters. First flowers appear 3-4 weeks after transplanting into garden.

Install sturdy cages or stakes early (indeterminate varieties grow 5-7 feet tall). Pinch off lower leaves as plant grows to improve air circulation. Fertilize every 2-3 weeks with balanced fertilizer or tomato-specific formula. Ensure consistent water to prevent flower drop.

4

Fruiting

4-5 weeks from fruit set to harvest

Green fruits develop from pollinated flowers, gradually enlarging. Fruits transition from green to dark red-purple, then deepen to nearly black at full maturity. The dark color is most pronounced in fruits receiving maximum sunlight.

Support heavy fruits with slings or cages as they enlarge. Maintain consistent watering to prevent cracking and blossom end rot. Continue light pruning of lower leaves but don't remove excessive foliage (provides fruit protection from sunscald). Monitor for pests and diseases. Full Black's dark color can make ripeness harder to assess—fruits should yield slightly to gentle pressure.

5

Harvest & Succession

8-12 weeks of harvest (until frost)

First fruits mature 75-85 days after transplanting. Indeterminate variety continues producing until first frost, with new flowers and fruits at different stages simultaneously.

Pick fruits when dark purple-black and slightly soft to touch. Harvest regularly to encourage more production. In late season, remove apical meristem (top growing point) 4 weeks before first expected frost to redirect energy to ripening existing fruits. Remove diseased foliage promptly.

Companion Planting

Plan your garden →

Plant with:

Avoid planting near:

Brassicas (cabbage, broccoli, kale) Fennel Dill Walnut trees Potatoes (same family; share pests/diseases)

Common Pests

  • Hand-pick large caterpillars; encourage parasitic wasps; apply Bt (Bacillus thuringiensis) for smaller infestations

  • Spray with insecticidal soap or neem oil; use yellow sticky traps; encourage native predators

  • Remove lower infected leaves; improve air circulation; apply copper fungicide or sulfur; avoid overhead watering

  • Remove infected plant parts immediately; apply preventive fungicide (copper or chlorothalonil) in wet conditions; ensure good drainage

  • Spray with strong water stream; apply insecticidal soap; release ladybugs or other natural predators

  • Increase humidity; spray with insecticidal soap or neem oil; encourage predatory mites

Uses

🍳

Fresh slicing and salads

Culinary

Full Black tomatoes have a rich, complex, slightly smoky flavor with low acidity, making them exceptional for fresh eating, slicing on platters, and in salads. Their deep color and robust taste elevate simple tomato-forward dishes. [source]

🍳

Sauces and preservation

Culinary

The meaty texture and intense flavor make Full Black ideal for homemade pasta sauces, salsas, and canning. Their concentrated taste produces deeply flavored, complex sauces. [source]

💊

Antioxidant health benefit

Medicinal

Dark-pigmented tomatoes like Full Black contain elevated levels of anthocyanins and other polyphenolic compounds in addition to standard lycopene, offering enhanced antioxidant potential. Regular consumption may support cardiovascular and cellular health. [source]

🏠

Ornamental garden display

Household

Full Black's striking dark fruits and vigorous indeterminate growth make it a visually stunning addition to vegetable gardens or landscape plantings, often grown as much for appearance as for production. [source]

🎨

Seed saving

Craft

As an heirloom variety, Full Black is an excellent candidate for seed saving. Seeds can be fermented, dried, and saved for multiple seasons, preserving this unique variety for years. [source]

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

Harvest Tips

Harvest when fruits are deep purple-black and yield slightly to gentle pressure (slightly softer than conventional red tomatoes). The dark color makes ripeness assessment challenging compared to red varieties—use gentle squeeze and color as indicators. Pick fruits in early morning for best flavor. Fully ripe fruits can be left on the plant for maximum flavor development. In cooler climates, harvest any remaining green fruits 2-3 weeks before first frost and ripen indoors in a paper bag.

Fun Facts

  • 🌱 Full Black is a Russian heirloom variety with origins in Eastern European tomato breeding, prized for its intense flavor and unusual dark coloration that develops from high anthocyanin content—the same compounds that make blueberries blue.
  • 🌱 The dark purple-black color intensifies when plants receive maximum sunlight; fruits grown in partial shade will be noticeably lighter in color and may appear more burgundy than black.
  • 🌱 Indeterminate Full Black plants can reach 6-7 feet tall and produce continuously until frost, making them prolific producers that can yield 50-100+ tomatoes per plant in favorable conditions.

Gardening Terms

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