Dwarf Perennial
Blue Butterfly Delphinium is a frost-hardy heirloom that brings vibrant summer color to cold-climate gardens, thriving even in Zone 3. This compact cultivar grows just 12 to 24 inches tall and produces the delicate, jewel-toned blue flowers that made delphiniums beloved by Victorian gardeners. Deer won't touch it, and pollinators flock to its spikes from June through August, making it both beautiful and ecologically generous.
12-15 inches apart
Full Sun
Moderate
3-3
24in H x 18in W
Perennial
High
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This little delphinium packs serious charm into a 12 to 24-inch frame, delivering full-sized delphiniums in a footprint small enough for containers or tight garden spaces. The blue flowers bloom reliably throughout summer in zones cold enough to stop most ornamentals, and their nectar draws bees and butterflies while deer leave them alone. Starting from seed is straightforward if you remember the one quirk: seeds need darkness to germinate, making this a rewarding project even for first-time growers.
Blue Butterfly Delphinium is grown entirely for its ornamental value. The spikes of blue flowers bring vertical interest to borders, cottage gardens, and cutting gardens throughout summer. Its compact size and cold hardiness make it especially valued in northern regions where other delphiniums may struggle.
Start seeds indoors 8 to 10 weeks before your last frost date. Sow seeds on the surface of sterile seed-starting mix with vermiculite, pressing gently without covering, as seeds need darkness for germination. Keep the soil at 65 to 70°F and maintain consistent moisture without waterlogging. Seeds typically sprout in 10 to 30 days.
Harden off seedlings by gradually exposing them to outdoor conditions over 7 to 10 days. Transplant after your last spring frost when soil has warmed and nighttime temperatures consistently stay above freezing. Space plants 1 inch apart in their final location.
Direct sow after the last spring frost through early summer, pressing seeds into the soil surface in a location with good air circulation and well-draining soil.
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“Blue Butterfly Delphinium carries the heritage of Delphinium grandiflorum, a species that has delighted gardeners for generations. This heirloom cultivar represents the kind of plant that families and seed savers have maintained and passed down, preserving the genetics that make it so reliably hardy and floriferous in northern climates. Its story is one of living history, kept alive by gardeners who recognize that sometimes the most elegant flowers come from humble, time-tested lineages.”