Delphinium
larkspurs
Temperate Northern Hemisphere and tropical African mountains
Overview
Delphinium spp. is a genus of about 300 species of annual, biennial, and perennial herbs in the buttercup family, Ranunculaceae, found across the temperate Northern Hemisphere and the high mountains of tropical Africa. Plants form clumps of palmately lobed or deeply divided leaves and send up erect flowering spikes 1–7 ft (30–210 cm) tall, with tall border hybrids reaching the upper end of that range. The flowers are borne in dense or open racemes and have five petal-like sepals, the uppermost drawn out into a backward-pointing spur, with smaller true petals at the center forming an eye. Flower color is dominated by blue and violet, with purple, white, pink, and red across the genus. The fruit is a cluster of dry follicles that split to shed flattened seeds. All parts contain diterpenoid alkaloids that are toxic to people and livestock, and the plants are a frequent cause of cattle poisoning on western North American ranges. Tall perennial species are short-lived and often need staking and replacement, while annual larkspurs complete their cycle in one season. The genus grows in meadows, woodland clearings, and mountain slopes.
Native Range
Delphinium spp. ranges across temperate Europe, Asia, and North America, with additional species in the mountains of tropical Africa. North American native species include D. nuttallianum and scarlet larkspur D. cardinale. The tall border delphiniums of gardens derive largely from the Eurasian D. elatum.Suggested Uses
Delphinium spp. species are grown at the back of borders, in cottage gardens, and as cut flowers for their tall spikes. Lower-growing and annual species are used in mixed beds and meadow plantings. The flowers attract bees and, in red-flowered species, hummingbirds.How to Identify
Appearance
Size & Dimensions
Height1' - 7'
Width/Spread1' - 3'
Bloom Information
Most perennial Delphinium spp. species flower in early to midsummer, roughly June to July, on tall terminal spikes. Cutting back spent spikes after the first flush can prompt a smaller second bloom in late summer. Annual larkspurs flower over a longer period from late spring into summer. Flower color is mainly blue and violet, with white, pink, and purple forms.
Detailed Descriptions
Flower Description
blue, violet, purple, white, pink, or redFoliage Description
greenGrowing Conditions
Sun Requirements
Requires 6-10 hours of direct sunlight daily
• Full Sun: 6+ hours of direct sunlight
• Partial Shade: 3-6 hours of direct sunlight
• Full Shade: Less than 3 hours of direct sunlight