Tweedia coerulea Heavenly Blue | Blue Milkweed

Tweedia coerulea Heavenly Blue | Blue Milkweed

Tweedia (Oxypetalum coeruleum) is a unique and captivating cut flower, treasured for its rare sky-blue blooms and long-lasting vase life. Specially bred for professional cut flower use, this compact and upright variety is perfect for both greenhouse and field production, but it also thrives in borders and ornamental plantings.

Although a true perennial, Tweedia is commonly grown as an annual in cooler climates, flowering within a few months from seed. Its wiry stems and delicate star-shaped blooms add elegance to any bouquet, making it a staple in wedding floristry and high-end arrangements.

Key Features:

• Type: Perennial (grown as an annual)
• Height: Up to 70 cm
• Stem Length: 50–60 cm
• Flowering Period: July to October
• Color: Spectacular sky-blue
• Vase Life: 10+ days
• Position: Full sun
• Soil: Moist but well-drained
• Spread: Approx. 75 cm
• Hardiness: Minimum temperature 5°C; frost-sensitive
• Common Name: Blue Milkweed

Sowing Instructions:

• Indoors:
  Start seeds 7–8 weeks before the last frost. Surface sow on moist, well-drained compost and cover lightly. Maintain a temperature of around 22°C. Germination can be erratic – typically 1–2 weeks but may take up to 3 months. Pot on and harden off before planting out after frost risk has passed.

• Outdoors:
  Sow directly into well-prepared soil after the last frost. Thin seedlings as required.

Growing Tips:

• Pinch young plants to encourage bushy growth.
• Provide support for taller stems.
• Water freely during active growth; reduce watering in winter.
• In frost-free areas or greenhouses, it can be overwintered as a perennial.
• Cut back or prune lightly in early spring if overwintered.

Propagation:
By seed or softwood cuttings in summer with bottom heat.

Why Grow Tweedia?

• Blooms from July to mid-September
• Long, sturdy stems (50–60 cm) ideal for cutting
• Resilient to wind and rain
• Rare, true-blue color for premium bouquets
• Excellent vase life – over 10 days

Ideal For:

• Cutting gardens
• Wedding arrangements
• Specialty cut flower production
• Containers or mixed borders (ornamental use)