How to Grow Ruby Ball

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Ruby Ball

Brassica oleracea var. capitata

vegetable

Ruby Ball is a compact, early-maturing red cabbage variety known for its deep crimson color and small, dense heads. It produces firm, round heads typically weighing 3-4 pounds, making it ideal for small gardens and container growing. The variety is prized for its vibrant color, sweet flavor, and reliable performance in both spring and fall seasons.

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

  1. Plant Ruby Ball

    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 Ball

    Around Jun 26

    ≈ 70 days after planting

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

Growing Conditions

☀️
Sun: Full sun, 6-8 hours daily minimum
💧
Water: Consistent moisture; water deeply 1-2 inches per week. Keep soil evenly moist but not waterlogged to prevent splitting and clubroot disease
📏
Spacing: 12-18 inches between plants inches
📅
Days to maturity: 70-85 days from transplant
🌱
Planting depth: 0.25 inches for seeds; transplants at soil line

Soil

Type: Rich, well-draining loamy soil with high organic matter
pH: 6.0-7.5
Amendments:
Compost aged manure bone meal calcium (lime if pH is low)

Growing Zones

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Thrives in zones 2-9; best in zones 3-8 for optimal color and flavor

2a 2b 3a 3b 4a 4b 5a 5b 6a 6b 7a 7b 8a 8b 9a

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Growth Stages

1

Seedling

4-6 weeks

Young plants with 2-4 true leaves, delicate and tender

Start seeds indoors 4-6 weeks before transplant date. Keep soil consistently moist and provide bright light. Thin seedlings to prevent overcrowding and weak growth.

2

Vegetative

3-4 weeks

Developing sturdy plants with expanding leaves, building root system and foliage

Transplant outdoors after last frost. Provide consistent water and light fertilization every 2-3 weeks. Mulch around plants to retain moisture and regulate soil temperature.

3

Head Formation

4-5 weeks

Leaves curl inward as the compact, round head begins to form and tighten

Maintain even soil moisture to prevent stress and splitting. Continue fertilizing with nitrogen-rich fertilizer. Monitor for pests closely during this critical period.

4

Head Maturation

2-3 weeks

Heads become dense, firm, and develop deep crimson color throughout the leaves

Reduce nitrogen fertilization; increase potassium to improve color and flavor. Water consistently but allow soil surface to dry slightly between waterings.

5

Harvest Ready

Varies by harvest timing

Heads are firm, compact, and deeply colored; outer leaves feel crisp and snappy

Check head firmness by gently squeezing. Harvest when heads reach 3-4 pounds. Can tolerate light frosts; flavor improves after light frost exposure.

Companion Planting

Plan your garden →

Plant with:

Avoid planting near:

Strawberries tomatoes fennel kohlrabi broccoli other brassicas within 3 feet

Common Pests

  • Use floating row covers; apply Bt (Bacillus thuringiensis) spray weekly starting at transplant; handpick larvae

  • Deploy row covers; spray neem oil or Bt; encourage parasitic wasps and natural predators

  • Use row covers on young plants; spray with neem oil; dust with food-grade diatomaceous earth

  • Spray with strong water stream; apply insecticidal soap; use reflective mulches; encourage ladybugs

  • Improve soil drainage; lime acidic soils; rotate crops; remove infected plants; practice strict sanitation

  • and

    Hand-pick; use copper barriers; apply slug bait; encourage ground beetles; remove debris shelters

Uses

🍳

Raw salads and slaws

Culinary

Ruby Ball's vibrant crimson color and crisp texture make it ideal for colorful slaws, salads, and garnishes. The slightly sweet flavor pairs well with vinaigrette dressings. [source]

🍳

Braising and roasting

Culinary

The dense heads hold up excellently to braising, roasting, and pickling. When cooked with vinegar or lemon, the color remains vibrant. [source]

💊

Antioxidant-rich superfood

Medicinal

Red cabbage is rich in anthocyanins, vitamins C and K, and beneficial sulfur compounds that support digestive health and immune function. [source]

🏠

Natural pH indicator

Household

Red cabbage extract can be used to create a natural pH indicator for science experiments due to its anthocyanin content changing color with acidity. [source]

🦋

Pollinator and predator support

Wildlife

Allowing some cabbage plants to flower attracts bees and beneficial insects while supporting parasitic wasps that control cabbage pests. [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 heads are firm and compact, typically 3-4 pounds in weight. Cut heads at the base using a sharp knife, leaving the stem and roots in place—secondary small heads may develop. Ruby Ball is cold-tolerant and flavor improves after light frost exposure (down to 28°F). For storage, harvest in dry conditions and store in cool, humid environment (32-40°F) for 2-4 months. Can leave heads in garden through light frosts for extended harvest.

Fun Facts

  • 🌱 Ruby Ball cabbage contains anthocyanins, the same powerful antioxidants found in blueberries and red wine, which give it its striking crimson color and potential health benefits.
  • 🌱 Red cabbage can be used as a natural pH indicator—when exposed to different pH levels, the anthocyanins change color from pink to blue to yellow, making it useful for science demonstrations.
  • 🌱 The variety was developed to address the gardener's need for compact, early-maturing red cabbage suitable for home gardens and small spaces, combining disease resistance with reliable, predictable head formation.

Gardening Terms

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

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