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How to Grow Ruby Princess Tomato

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Ruby Princess Tomato

Solanum lycopersicum 'Ruby Princess'

vegetable

Ruby Princess is a determinate (bush-type) tomato variety known for producing abundant medium-sized fruits with a deep red color and excellent flavor. This compact plant is ideal for container growing and small spaces while still delivering high yields. It matures relatively quickly and is popular for fresh eating and sauce-making.

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Example Ruby Princess Tomato timeline · Pittsburgh, PA (Zone 6b)

  1. Plant Ruby Princess 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 Ruby Princess Tomato

    Around Jun 21

    ≈ 65 days after planting

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

Growing Conditions

☀️
Sun: Full sun, 6-8 hours daily (8+ hours optimal)
💧
Water: Consistent moisture, 1-2 inches per week; water deeply at soil level to avoid wetting foliage; reduce frequency slightly once fruiting begins to concentrate sugars
📏
Spacing: 24-36 inches
📅
Days to maturity: 65-75 days from transplant
🌱
Planting depth: 0.25 inches for seeds; transplants set 2-3 inches deeper than container to encourage root development

Soil

Type: Well-draining loamy soil rich in organic matter
pH: 6.0-6.8
Amendments:
Compost aged manure peat moss perlite for drainage calcium (lime or gypsum to prevent blossom end rot)

Growing Zones

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Thrives in zones 5-9; can be grown seasonally in zones 3-4 and 10+ with protection

3a 3b 4a 4b 5a 5b 6a 6b 7a 7b 8a 8b 9a 9b 10a 10b

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Growth Stages

1

Seedling

2-3 weeks

Small seedlings with 2-4 true leaves; cotyledons (seed leaves) initially visible

Provide bright light 14-16 hours daily; maintain soil moisture but avoid waterlogging; keep at 65-75°F; thin to strongest seedling if direct-seeded

2

Vegetative Growth

3-4 weeks

Rapid stem and leaf development; plant becomes bushy with increasing leaf surface; no flowers yet

Harden off transplants gradually before field planting; apply balanced fertilizer every 2 weeks; support with small stake if needed; pinch terminal bud on determinate types only if overly vigorous

3

Flowering

2-3 weeks

Yellow flowers appear in clusters; plant reaches near-final height; flower buds and early blooms visible

Switch to lower-nitrogen fertilizer (higher phosphorus); maintain consistent watering to prevent flower drop; spray foliage with water in hot weather to cool plant; avoid over-fertilizing which delays fruiting

4

Fruiting & Early Ripening

2-3 weeks

Small green fruits develop from flowers; fruits enlarge; plant may appear slightly stressed; first color change from green to orange-red begins

Maintain steady water supply; avoid wetting fruit directly; provide additional stakes/cages if fruit load is heavy; light pruning of lower leaves improves air circulation; reduce nitrogen fertilizer

5

Harvest & Production

3-6 weeks (or until frost/disease limits productivity)

Fruits ripen to deep red; plant reaches maximum productivity; older leaves may yellow naturally

Pick ripe fruits regularly to encourage continued production; harvest mature-green fruits if disease or frost threatens; continue consistent watering; remove diseased leaves promptly; monitor for late blight in humid regions

Companion Planting

Plan your garden →

Plant with:

Basil parsley marigold nasturtium carrot onion garlic borage sage

Avoid planting near:

Cabbage brassicas fennel dill other nightshades (potato, eggplant, pepper) - risk of shared pests/diseases

Common Pests

  • Hand-pick larvae; encourage natural parasitoid wasps; spinosad spray; neem oil; Bt (Bacillus thuringiensis)

  • Strong water spray; neem oil; insecticidal soap; increase humidity; reflective mulch

  • Yellow sticky traps; insecticidal soap; neem oil; encourage natural predators; reflective mulch

  • Remove lower infected leaves; improve air circulation; mulch to prevent soil splash; copper fungicide; chlorothalonil spray

  • Avoid overhead watering; copper fungicide; mancozeb; chlorothalonil; resistant varieties; remove infected plants

  • Remove infected leaves; improve air circulation; copper fungicide; avoid wetting foliage; stake/prune for airflow

Uses

🍳

Fresh Eating & Salads

Culinary

Ruby Princess tomatoes have excellent flavor with balanced sweetness and acidity, making them ideal for slicing into salads, sandwiches, and fresh preparations. Their medium size and meaty texture also work well for halving and serving as appetizers. [source]

🍳

Sauce & Preserving

Culinary

The high pectin content and solid fruit structure make Ruby Princess suitable for making tomato sauce, paste, and canning. Their determinate nature produces concentrated harvests perfect for processing batches. [source]

💊

Nutrition & Antioxidants

Medicinal

Tomatoes are rich in lycopene, a powerful antioxidant associated with heart and cancer health benefits. Ruby Princess's deep red color indicates high lycopene concentration. [source]

🏠

Garden Production

Household

Ruby Princess's compact determinate form and high yield make it excellent for home gardeners with limited space, container gardens, or small urban plots seeking maximum productivity. [source]

🦋

Pollinator Support

Wildlife

Tomato flowers attract bees and other pollinators to the garden, supporting broader ecosystem health and potentially improving fruit set on other plants in the vicinity. [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 fully red and slightly soft to gentle pressure; morning picking after dew dries ensures best flavor; for determinate varieties like Ruby Princess, expect concentrated harvest window of 2-3 weeks; harvest mature-green fruits (full size, pale green or color break visible) 7-10 days before frost to ripen indoors

Fun Facts

  • 🌱 Ruby Princess is a determinate 'bush' variety, meaning it stops growing at a predetermined height (typically 3-4 feet) and sets most of its fruit within a short window, making it ideal for canning and processing—unlike indeterminate 'vining' varieties that produce fruit all season.
  • 🌱 Tomato plants can be induced to set more fruit by reducing nitrogen fertilizer once flowering begins; excess nitrogen promotes leafy growth at the expense of flowers and fruit.
  • 🌱 Tomatoes planted deeper than their seedling depth develop roots along the buried stem, creating a stronger, drought-resistant root system—a technique especially useful in hot or dry climates.

Gardening Terms

New to gardening? Learn about terms used in this guide:

Full Sun pH Transplant True Leaves
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