Delphinium grandiflora
Chinese Delphiniums
Cold Winters |
Mild Winters |
Sun/Shade |
Sow Seeds |
Days to Germinate |
Mature Height |
---|---|---|---|---|---|
March – May |
Feb. – April |
Full sun |
1 in. apart |
21 – 28 days |
18 – 24 inches |
PERENNIAL/BLOOMS FIRST YEAR
Summer/fall bloom
Hardy to Zone 3
START EARLY INDOORS
In spring, 8 to 10 weeks before last expected frost, sow seeds 1 inch apart in a container of seed starting mix. Cover 1/4 inch deep, keep moist and provide a strong light source until seedlings are ready to plant outdoors. Feed seedlings every 2 weeks with half-strength fertilizer. Once large enough to handle, transplant seedlings 3 inches apart into deeper containers so root systems have room to develop. When plants are 3 to 4 inches tall, gradually acclimate to outdoor conditions and transplant 10 to 12 inches apart into a sunny garden spot with well-drained soil.
GROWING NOTES
Sow Blue Mirror in early spring for mid-summer flowers the first year, late spring bloom in subsequent years. Plants can handle more summer heat than the traditional delphinium varieties. Patrol for snails and slugs on new leaves and shoots. When each flush of flower finishes, cut stalks back to plant base to encourage reblooming. Water well and fertilize regularly throughout the growing season. Plants will die back and go dormant in winter. Leave dead foliage until early spring so you know where plants are, but cut the dead branches off at first signs of new spring growth.