larkspur

or delphinium

Any of 365 species of herbaceous plants that make up the genus Delphinium in the buttercup family, many of which are grown for their showy flower stalks. Annual larkspurs (sometimes separated as the genus Consolida) include the common rocket larkspur (D. ajacis, or C. ambigua) and its varieties, up to 2 ft (60 cm) tall, with bright blue, pink, or white flowers on branching stalks. Perennial larkspurs, often with blue flowers, include species that grow to 4.5 ft (1.4 m).

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