How to Grow Purple Flowering Choy Sum
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Purple Flowering Choy Sum
Brassica rapa subsp. parachinensis
vegetablePurple Flowering Choy Sum is an ornamental and edible Asian green featuring tender stems and purple flowers. It's a quick-growing brassica that produces delicate, nutritious greens and edible flower buds. This variety combines visual appeal with culinary versatility, making it ideal for both kitchen gardens and ornamental plantings.
When should you plant Purple Flowering Choy Sum in your zone?
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Example Purple Flowering Choy Sum timeline · Pittsburgh, PA (Zone 6b)
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Plant Purple Flowering Choy Sum
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 Flowering Choy Sum
Around Jun 1≈ 45 days after planting
Sample dates for Pittsburgh, PA. Sign up to get exact Purple Flowering Choy Sum dates for your own zip code.
Growing Conditions
Soil
Growing Zones
Find your zone →Thrives in zones 3-10; prefers cooler seasons in zones 8+
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Get my Purple Flowering Choy Sum timeline →Growth Stages
Seedling
2-3 weeksTiny true leaves emerge within 7-10 days; cotyledons pale green with compact growth
Thin seedlings to proper spacing early to prevent crowding. Maintain consistent moisture and provide bright light. Protect from wind and direct heat stress.
Vegetative
2-3 weeksTrue leaves develop; plant forms rosette with 4-6 leaves; stems begin to elongate slightly
Water consistently and apply balanced fertilizer every 2 weeks. Ensure adequate sunlight to prevent leggy growth. Begin side-dressing with compost.
Pre-Flowering
1-2 weeksMain stem elongates; leaf size increases; flower buds begin to form at stem tips; characteristic purple color intensifies
Increase watering frequency in warm weather. Maintain adequate nitrogen nutrition. Monitor for heat stress; provide afternoon shade if temperatures exceed 75°F (24°C).
Flowering & Harvest
2-4 weeksPurple flowers open on main stem and side shoots; small tender flower buds appear; leaves tender and flavorful at peak
Begin harvesting flower buds and tender stems once flowers appear. Regular harvesting encourages more side shoots and extends production. Water consistently to prevent wilting.
Decline
1-2 weeksFlowers fully open; stems become tougher and more fibrous; plant begins to bolt and set seed; leaf flavor may become bitter
Plan succession plantings for continuous harvest. Remove spent plants and replant. In cool seasons, cool-season crops can be extended with shade cloth.
Companion Planting
Plan your garden →Plant with:
Avoid planting near:
Common Pests
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Row covers until flowering; Bacillus thuringiensis (Bt); hand-picking; insecticidal soap
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Row covers; neem oil; diatomaceous earth; yellow sticky traps; reflective mulches
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Strong water spray; insecticidal soap; neem oil; beneficial insects like ladybugs; reflective mulches
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Yellow sticky traps; neem oil; insecticidal soap; reflective mulches
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Crop rotation; improve drainage; lime to raise soil pH; resistant varieties; remove infected plants immediately
Uses
Stir-frying and Asian cuisine
CulinaryThe tender stems, leaves, and purple flower buds are prized in Asian cooking, particularly Chinese cuisine. They have a mild, slightly sweet flavor and delicate texture that work beautifully in stir-fries, soups, and steamed dishes. [source]
Salads and raw preparation
CulinaryYoung leaves and tender flower buds can be eaten raw in salads for a delicate, slightly peppery flavor. The purple flowers add visual appeal and gentle brassica flavor to mixed green salads. [source]
Nutritional and antioxidant benefits
MedicinalPurple flowering choy sum is rich in vitamins A, C, and K, plus glucosinolates and anthocyanins (the purple pigments). These compounds support immune function, bone health, and possess potential anti-cancer properties studied in brassicas. [source]
Ornamental garden interest
HouseholdWith its attractive purple flowers and delicate form, purple flowering choy sum serves dual purpose as an edible-ornamental crop. The flowers attract pollinators and add color to vegetable and flower garden beds. [source]
Edible flowers for decoration
CraftThe small purple flowers can garnish plates, desserts, and cocktails. They're mild-flavored and visually striking, making them popular with chefs for elegant plating and culinary presentation. [source]
This is not medical advice. LizPlants is not a medical resource. Always consult a qualified healthcare professional before using plants medicinally.
Harvest Tips
Begin harvesting flower buds when they are small and tight (before flowers fully open) for best tenderness and flavor. Cut the main stem first, which encourages productive side shoots. Harvest stems and leaves regularly to extend production and prevent bolting. Morning harvest yields crispest greens. Cut 2-3 inches from the base, leaving lower leaves to regenerate. Entire plant can be harvested at once if preferred. Purple flower buds are peak flavor and most tender at early bloom stage.
Fun Facts
- 🌱 Purple Flowering Choy Sum's color comes from anthocyanin pigments, the same compounds that give blueberries their color and are associated with numerous health benefits.
- 🌱 Choy sum translates to 'flowering vegetable' in Cantonese (菜心), and has been cultivated in China for over 2,000 years; the purple flowering variety is a modern ornamental selection.
- 🌱 Unlike many brassicas, purple flowering choy sum is heat-tolerant relative to other leafy greens and can produce even in warm weather if given afternoon shade and consistent moisture.
Gardening Terms
New to gardening? Learn about terms used in this guide:
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