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Giant Imperial Mixture Larkspur is a towering annual that transforms gardens with dramatic spikes of color, reaching 36 to 48 inches tall and flowering in 77 to 84 days. This open-pollinated Delphinium consolida produces vivid blooms in blues, purples, pinks, and whites all at once, creating a garden-ready mix that thrives in full sun across hardiness zones 3 to 10. Strong, sturdy stems and feathery foliage make it a favorite for fresh cutting and drying, adding both height and texture to spring and early summer beds.
Full Sun
Moderate
3-10
48in H x ?in W
—
High
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Giant Imperial Mixture stands tall among larkspurs with densely packed flower spikes that deliver color in every direction. The mix of blues, purples, pinks, and whites creates a naturally cohesive palette without the need to plan companion colors. Its feathery foliage adds an airy, romantic texture that frames the bold blooms, and those strong stems hold up beautifully both in the garden and in a vase for weeks.
Giant Imperial Mixture Larkspur is grown primarily as a cutting flower, valued for its tall, elegant spikes that fill arrangements with height and movement. It's equally at home dried, retaining its vibrant color and shape long after harvest, making it popular for dried arrangements and wreaths.
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Start seeds indoors 6 to 8 weeks before your last spring frost. Sow seeds lightly on top of moist soil or press them in gently, as they need light to germinate. Keep soil temperatures around 60 to 65 degrees Fahrenheit and provide consistent moisture until seedlings emerge, usually within 10 to 14 days.
Transplant seedlings outdoors after the last frost date once they've developed their first true leaves and have been hardened off over 7 to 10 days. Space plants 10 inches apart and rows 18 inches apart. Larkspur tolerates cool soil, so transplanting can occur as soon as soil is workable in spring.
Direct sow seeds in early spring as soon as soil can be worked, pressing seeds lightly into the soil surface. Thin seedlings to 10 inches apart once they've developed true leaves. Direct sowing often produces more vigorous plants and stronger root systems than transplanting.
Cut flower spikes for arrangements when the lower blooms along the spike are fully open but the uppermost buds are still tight; this stage provides the longest vase life. Cut in early morning when stems are full of water. For drying, harvest spikes when fully colored but before flowers begin to fade, then hang upside down in a dark, well-ventilated space for 2 to 3 weeks.
Deadhead spent flower spikes regularly to encourage continued blooming throughout the season. For cut flower production, harvest spikes when the lower flowers are fully open but the top buds remain tight; this promotes new spike development lower on the stems.
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