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Cornflower 'Blue Diadem'
Seed Packet

Cornflower 'Blue Diadem'

Centaurea cyanus
The 1970s-era 'Blue Diadem' is a tall, strong-stemmed variety with large flowers of true blue. Easy to grow and excellent cut, it offers up scads of double flowers with violet centers all season long in moderate summer areas.
SKU #S1439OG
$3.50
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Details
Approximate Seeds Per Packet
125
Lifecycle
Annual
Annual Hardiness
Hardy Annual
Mature Size
2.5' h x 10" w
Sun
Full sun
Soil
Regular, well-drained
Season
Spring to summer
Color
Deep blue
Features
Great Cut Flower
Deer Resistant
Heat or Drought Tolerant
Attracts Bees
Attracts Beneficial Insects
Notable
Certified Organic Seed Available
SOWING INSTRUCTIONS
Depth:
Barely cover (about 1/16").
Sprout Time:
5-20 days
Seed To Bloom:
10 weeks
Starting Indoors:
Not recommended.
Starting Outdoors:
Sow in early spring, 3-4 weeks before last frost. Can also be fall sown (Oct.) in zones 7-10.
PLACEMENT & CULTIVATION
Cornflower Blue Diadem are sentimental favorites and of easiest culture, the numerous bees buzzing around the blooms a clue to their value in pollinator gardens. Try an early to mid-fall sowing in zones 7-10 for vigorous blooming plants earlier in the season. At home in the cutting garden, veggie garden, border, and meadow garden, they continue in bloom if picked often for bouquets both fresh and dried. Pull some edible petals to brighten up salads, freeze inside ice cubes, and more. Self sows.
Final Spacing:
8"
Water Requirements:
Medium Water Use
Watering Details:
Somewhat drought tolerant once established. 1" of water per week initially, then water during dry spells.
Soil pH:
Neutral to alkaline
Fertilizer:
Mix in about 1/2" of compost or an organic granular fertilizer prior to planting.
Diseases & Pests:
Avoid fungal troubles by placing in a location that has good air circulation.
When to Cut for Bouquets:
Beginning to open
Growing Guides Fall Sowing Hardy Annuals
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