Hybrid Delphinium
Guardian Blue Delphinium is a striking F1 hybrid that brings superior uniformity and reliability to the garden, a significant achievement in delphiniums, flowers notorious for their variability. These tall, stately plants produce magnificent spikes of deep blue flowers that reach their full glory in 105-125 days, making them a dependable choice for gardeners in zones 3-7 who crave the drama of cottage garden classics. Their compact 12-inch spacing allows you to create striking garden tapestries without excessive room requirements, while their exceptional longevity as cut flowers ensures your bouquets last week after week.
24-36 inches apart
Partial Shade
Moderate
3-7
?in H x ?in W
Perennial
High
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What sets Guardian Blue apart is its hybrid vigor and uniformity, you're not gambling with unpredictable heights or flower density like traditional delphiniums demand. This variety thrives in partial shade, a genuine advantage in warmer zones where afternoon sun can stress these cool-loving perennials. The flowers continue blooming into late summer and early fall if you deadhead promptly after the first flush, extending your garden's peak season considerably. Its strong suitability as a cut flower means you can enjoy these magnificent blue spikes indoors while still enjoying them in the border.
Guardian Blue Delphinium excels as a cut flower, delivering long-lasting arrangements that hold their color and form for an impressive span in the vase. These flowers are prized by florists and home arrangers alike for their architectural strength and ability to anchor floral designs with their towering, densely-packed blooms.
Sow seeds 10-16 weeks before your planned transplant date, covering them lightly with soil. Grow seedlings at 50-55°F (18-21°C) in a greenhouse or cold frame. When seedlings have developed true leaves, transplant them into larger cell packs or 3-4 inch containers about 6-8 weeks after germination. Harden off thoroughly by gradually exposing them to outdoor conditions before transplanting after the last frost.
Transplant outside after the last frost date once seedlings have been hardened off. Space plants 12 inches apart in a location that receives partial shade. If growing in a greenhouse, plugs can be transplanted into raised beds from August through September for earlier flowering.
For cut flowers, harvest when 1/4 to 1/3 of the flowers on the spike are open, cutting stems in early morning when they're most turgid. Place immediately in water upon cutting. Expect blooms to continue developing as the vase life extends, creating an ever-opening display.
Deadhead spent flower spikes immediately after the first bloom to encourage a second flush of flowers in late summer and early fall. This practice significantly extends the ornamental season and maintains the plant's vigor.
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