How to Grow Purple Ball
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Purple Ball
Brassica oleracea var. capitata f. rubra
vegetablePurple Ball is a purple or red cabbage variety known for its compact, round heads and vibrant deep purple coloration. It's a cool-season brassica that develops sweet, tender leaves when grown in proper conditions. This variety is prized for both culinary use and ornamental appeal in vegetable gardens.
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Example Purple Ball timeline · Pittsburgh, PA (Zone 6b)
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Plant Purple Ball
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 Purple Ball
Around Jun 26≈ 70 days after planting
Sample dates for Pittsburgh, PA. Sign up to get exact Purple Ball dates for your own zip code.
Growing Conditions
Soil
Growing Zones
Find your zone →Thrives in zones 3-9; prefers cool seasons for best color and flavor
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Seedling
3-4 weeksSmall plants with 2-4 true leaves, developing the characteristic blue-green cabbage foliage with purple tinting
Keep soil consistently moist. Maintain temperatures of 60-70°F. Provide 12-16 hours of light daily under grow lights if starting indoors. Thin or transplant to prevent overcrowding.
Vegetative Growth
4-6 weeksPlant develops larger rosette of deeply lobed leaves with prominent purple coloration. Leaf count increases rapidly as plant establishes strong root system.
Maintain consistent watering and moderate nitrogen fertilizer. Monitor for cabbage worms and looper caterpillars. Keep soil cool with mulch. Remove any yellowing outer leaves.
Head Formation
4-8 weeksLeaves begin to overlap and curl inward, forming a compact, dense purple head. The head gradually firms up and rounds out.
Reduce nitrogen, increase potassium and phosphorus fertilizer to support head development. Maintain even soil moisture to prevent cracking. Check regularly for pest damage. Continue removing diseased leaves.
Head Maturation
2-3 weeksHead becomes firm, dense, and deeply purple with a characteristic waxy bloom. The head reaches full size and weight, leaves are tightly wrapped.
Reduce watering slightly if heads begin to crack. Watch for cabbage moths and diamondback moths. Avoid excessive nitrogen which delays maturity. Begin harvesting when heads feel firm to pressure.
Harvest Ready
Harvest window varies; can extend 2-4 weeksHead is firm, dense, with vibrant deep purple color. Weight is substantial and head resists pressure when squeezed gently.
Harvest before hard frost for best quality. Cut heads at soil line with sharp knife. Can be stored in cool conditions for extended periods. Pull entire plant if necessary.
Companion Planting
Plan your garden →Plant with:
Avoid planting near:
Common Pests
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Use row covers on young plants. Apply Bacillus thuringiensis (Bt) spray when caterpillars appear. Hand-pick larger larvae. Plant companion herbs like thyme and sage to deter.
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Monitor leaf undersides for small green larvae. Remove infested leaves. Apply neem oil or insecticidal soap. Use row covers in early season. Maintain good air circulation.
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Apply Bt when small caterpillars appear. Encourage beneficial insects like parasitic wasps. Hand-pick larger green caterpillars. Use pheromone traps to monitor populations.
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Use row covers on seedlings and transplants. Apply diatomaceous earth to foliage. Use sticky traps. Apply neem oil if infestation is severe. Remove infested leaves.
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Spray strong water stream to dislodge. Apply insecticidal soap or neem oil. Release ladybugs or parasitic wasps. Encourage natural predators with flowering plants.
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Practice crop rotation (3-4 year minimum). Maintain soil pH above 6.0. Use disease-resistant varieties if available. Remove infected plants immediately. Disinfect tools between plants.
Uses
Raw Salads & Slaws
CulinaryPurple cabbage's crisp texture and mild, slightly sweet flavor make it ideal for fresh salads, coleslaws, and raw vegetable platters. The vibrant purple color adds visual appeal to dishes. [source]
Cooked Dishes & Fermentation
CulinaryPurple cabbage can be steamed, sautéed, roasted, or fermented into sauerkraut and kimchi. Cooking enhances sweetness and tenderness while fermentation provides probiotics and extends shelf life. [source]
Nutritional & Antioxidant Support
MedicinalRich in anthocyanins, vitamin C, and other antioxidants, purple cabbage supports immune function and may help reduce inflammation. Its nutrients are best preserved through light cooking or raw consumption. [source]
Natural pH Indicator
HouseholdPurple cabbage juice can be used as a natural pH indicator in science experiments, turning pink in acidic solutions and blue-green in alkaline solutions. This demonstrates interesting chemical principles. [source]
Butterfly & Pollinator Support
WildlifeIf allowed to flower (in cool climates or second-year growth), purple cabbage produces attractive yellow flowers that attract bees and other pollinators, supporting garden biodiversity. [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 feel firm and dense when squeezed gently, typically 70-120 days after transplanting depending on variety and season. Cut heads at the base with a sharp knife, leaving roots in soil (they may produce smaller secondary heads). For longest storage, harvest after a light frost, which improves sweetness. Store in cool (32-40°F), humid conditions for 3-4 months. Can be harvested at any size, but allow full maturity for maximum flavor and storage potential.
Fun Facts
- 🌱 Purple cabbage gets its deep color from anthocyanins, the same pigments found in blueberries and red wine. These powerful antioxidants have been studied for potential health benefits including anti-inflammatory and anti-cancer properties.
- 🌱 In traditional European cuisine, purple cabbage is often pickled with vinegar and spices, creating a tangy condiment called 'Rotkohl' in German cooking. This pickling process was historically used for winter food preservation.
- 🌱 Purple cabbage plants can be grown as cool-season ornamentals in fall and winter gardens, providing both food production and striking visual interest with their deep purple coloration and rounded heads.
Gardening Terms
New to gardening? Learn about terms used in this guide:
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