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Tweedia 'Heavenly Blue'
Seed Packet

Tweedia 'Heavenly Blue'

Oxypetalum caeruleum
The rarest of flower colors–sky blue–is found in these starry flowers. Washed with a hint of turquoise blue and tiny freckles, they should be grown in containers to enjoy the clustered blooms in summer fully. Also called blue star milkweed, it develops long, gracefully curving pods that enclose the seeds.
SKU #S1796
$4.25
Details
Approximate Seeds Per Packet
22
Lifecycle
Annual; tender perennial
Perennial Hardiness Zone
10
Annual Hardiness
Tender Annual
Mature Size
2' h x 2' w
Sun
Full sun to partial shade
Soil
Regular, moist, well-drained
Season
Summer to fall
Color
Powder blue with hints of turqoise
Features
Scented Leaves
Great for containers
Deer Resistant
Attracts Butterflies
Attracts Bees
SOWING INSTRUCTIONS
Depth:
Surface sow
Sprout Time:
7-14 days
Seed To Bloom:
12-14 weeks
Starting Indoors:
Recommended. Sow in pots 8 weeks before last frost, cover lightly with vermiculite or a humidity dome and keep at 68-75F.
Starting Outdoors:
Direct sow after frost.
WHEN TO SET OUTSIDE
About 2 weeks after last frost, when temperatures remain above 50°F.
PLACEMENT & CULTIVATION
Tweedia hails from Brazil, where it grows large. In northern areas it grows slowly at first, its clusters of powder-blue flowers with a watercolor wash of turquoise start to bloom by midsummer. Part of the milkweed family, and often called blue milkweed for the slim curved pods enclosing silky seeds that develop in fall. Best in a container in a sheltered sunny spot protected from rain and wind storms that will damage their delicate flowers. Nonetheless, it will continue to bloom throughout fall and can spend the winter indoors as a blooming houseplant. Provide support when setting out and pinch once to encourage branching.
Final Spacing:
1-1.5'
Water Requirements:
Medium Water Use
Watering Details:
1" of water per week.
Soil pH:
Acidic to neutral
Fertilizer:
One application of organic fertilizer midseason as buds form
Diseases & Pests:
No serious diseases or pests. Milkweed aphids can infest late in the season and can be controlled by insecticidal soaps.