How to Grow Purple Danish
Purple Danish
Brassica oleracea var. capitata f. rubra
vegetablePurple Danish is a red/purple cabbage variety known for its dense, compact heads and deep violet coloring. It offers excellent storage capabilities and a slightly sweeter, more tender flavor than green cabbage varieties. This heirloom cultivar is prized for both fresh use and pickling.
When should you plant Purple Danish in your zone?
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Example Purple Danish timeline · Pittsburgh, PA (Zone 6b)
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Plant Purple Danish
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 Danish
Around Jul 1≈ 75 days after planting
Sample dates for Pittsburgh, PA. Sign up to get exact Purple Danish dates for your own zip code.
Growing Conditions
Soil
Growing Zones
Find your zone →Thrives in zones 2-9; prefers cooler seasons for best color and quality
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Seedling
4-6 weeksSmall plants with 2-4 true leaves, pale purple-green coloring
Keep soil consistently moist. Provide bright light. Thin seedlings to prevent crowding. Begin hardening off 7-10 days before transplanting.
Vegetative/Establishment
3-4 weeks post-transplantYoung transplants establishing root systems and producing 6-12 leaves, developing darker purple coloration
Transplant after last frost. Space 18 inches apart. Water deeply 2-3 times weekly. Mulch around base to retain moisture and suppress weeds. Apply balanced fertilizer every 3-4 weeks.
Head Formation
4-6 weeksCompact purple heads beginning to form at the center, leaves wrapping tightly; plant reaches full size
Maintain consistent watering and soil moisture—critical for head development. Apply calcium-rich fertilizer to prevent tip burn. Monitor for cabbage moths and imported cabbageworms. Remove any damaged outer leaves.
Head Maturity
2-3 weeksDense, solid purple heads firm to slight pressure; deep violet color fully developed; heads reach 4-6 inches diameter
Continue monitoring water consistency. Stop fertilizing 2-3 weeks before harvest. Deep purple color is best indicator of maturity. Heads should be hard when squeezed.
Harvest
1-2 weeks optimal harvest windowMature heads ready for cutting; outer leaves protective and intact
Harvest when heads feel solid and firm. Cut with a sharp knife at the base. For storage, keep outer leaves on the head. Harvest before heavy frost if storing long-term.
Companion Planting
Plan your garden →Plant with:
Avoid planting near:
Common Pests
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Row covers, Bacillus thuringiensis (Bt), hand-picking eggs and larvae, netting
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Insecticidal soaps, neem oil, spinosad, beneficial insects like parasitic wasps
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Bt spray, spinosad, handpicking, row covers
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Row covers, insecticidal soap, neem oil, reflective mulches
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Strong water spray, insecticidal soap, neem oil, beneficial insects
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Improve drainage, lime application to raise pH, crop rotation, resistant varieties
Uses
Fresh cooking and salads
CulinaryPurple Danish cabbage offers a slightly sweet, tender flavor excellent for slaws, salads, and stir-fries. The deep purple color makes it visually striking in fresh dishes. [source]
Pickling and preservation
CulinaryTraditional European pickling use; the firm texture holds well through pickling processes. Creates beautiful purple-hued pickled vegetables. [source]
Nutritional and anti-inflammatory
MedicinalRed cabbages are rich in anthocyanins and vitamin C with potential anti-inflammatory benefits. Traditionally used in folk medicine for digestive and circulatory support. [source]
Natural pH indicator
HouseholdThe anthocyanin pigments in purple cabbage can be extracted to create natural pH indicator solutions used in science experiments and food coloring. [source]
Pollinator and beneficial insect support
WildlifeWhen allowed to bolt, cabbage flowers attract bees and beneficial insects. Attracts parasitic wasps that control common brassica 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 fully colored (deep purple/violet). Heads typically reach 4-6 inches in diameter. Cut at the base with a sharp knife, leaving some stem and outer leaves for protection. For storage, keep outer leaves intact. Purple Danish stores exceptionally well in cool (32-40°F), humid conditions for 2-4 months. Harvest in fall for best storage; spring plantings are best used fresh.
Fun Facts
- 🌱 Purple Danish is an heirloom variety that has been cultivated since the 19th century in Denmark, selected for its exceptional storage qualities and deep color.
- 🌱 The purple/red color comes from anthocyanin pigments, which are antioxidants that become more vibrant when grown in cooler temperatures, making fall crops superior to spring plantings.
- 🌱 Purple cabbage juice was historically used as a natural dye and can indicate pH changes—turning pink in acidic conditions and blue-green in alkaline solutions.
Gardening Terms
New to gardening? Learn about terms used in this guide:
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