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Delphinium

Delphinium (del-FIN-ee-um)

Family: Ranunculaceae Native Herbaceous (3-15 ft)

Delphinium is a genus of herbaceous, flowering plants containing more than 500 species from temperate and subtropical regions of North America, Europe, Africa and Asia. The species, commonly called larkspurs, include annuals, biennials, and perennials and can often be found growing wild in forests or natural areas in rich woods and in mountains. Delphinium is a member of the buttercup family (Ranunculaceae). Its native range is eastern and northern Asia. The genus name comes from the Greek word " delphis " meaning "dolphin," in reference to the flower bud shape of some species resembling a dolphin. Delphiniums do best in fertile, medium moisture, well-drained soils in full sun and tolerate alkaline soils. The plant prefers cool summers but will do well if protected with afternoon shade in hot summer climates. Bloom time is May through mid-summer. It can be a challenge to grow them in humid summer climates south of USDA Zone 7. Delphiniums require considerable maintenance (staking, pruning, deadheading, disease control) in order to perform well in the garden. Plants, especially taller varieties, require protection from strong winds and rainstorms by means of shelter and staking. As a short-lived perennial, spent flowers should be promptly cut back to the basal foliage to encourage additional late summer and fall blooms. Some delphiniums spread in disturbed areas in woods and fields and can become weedy in gardens. Most of the plants sold commercially are complex hybrids. These incredibly showy flowers have their own category for Award as Garden of Merit in the Royal Horticultural Society. Delphinium-specific trials of merit have been in progress since 1916, transitioning in 1925 to an established annual best cultivar award. These beauties attract birds and hummingbirds with flowers ranging in color from blue, pink, lavender and white. This plant is toxic to humans and pets. Delphiniums do well as border plants and in mass plantings. They are well-suited to woodlands, meadows and naturalized areas. They are often featured in cottage gardens. Diseases, Insect Pests, and Other Plant Problems: Delphiniums are susceptible to powdery mildew, botrytis blight, leaf spots and crown rot. Plants in full sun generally show better resistance to powdery mildew. Crown rot will inevitably develop if plants are grown in poorly drained soils or planted too deep. Slugs and snails can do significant damage. Watch for aphids, leaf miners, stem borers and mites.

Source: NC State Extension Gardener Plant Toolbox ↗ NC State Extension Gardener Plant Toolbox, 53 attributes.

How it fits the guild

Guild layer 4 - Herbaceous (3-15 ft) Optimal soil pH Alkaline (>8.0)
See companions & conflicts ↓

Companions & Conflicts

Curated pairwise relationships between this plant and others in the library — who feeds whom, who competes, who confuses the pests. Green reads as a good pairing, red as one to avoid.

No curated interactions recorded for this species yet.

Also noted by NC State

Related species the NC State Plant Toolbox flags for this plant — look-alikes to tell apart, and plants that play a similar role in a planting. Ones we carry in the library are linked.

Often confused with Salvia sagittata

Full plant profile

Growing Conditions
Plant type
Annual; Herbaceous Perennial; Native Plant; Poisonous
Life cycle
Annual; Perennial
USDA zones
3a, 3b, 4a, 4b, 5a, 5b, 6a, 6b, 7a, 7b, 8a, 8b, 9a, 9b
Light
Full sun (6 or more hours of direct sunlight a day) | Partial Shade (Direct sunlight only part of the day, 2-6 hours)
Soil texture
High Organic Matter
Soil pH
Alkaline (>8.0)
Soil drainage
Good Drainage
Available space
Less than 12 inches
NC region
Coastal; Mountains; Piedmont
Mature size
Height: 1 ft. 0 in. - 3 ft. 0 in. | Width: 1 ft. 0 in. - 2 ft. 0 in.
Maintenance
High
Canopy layer
4 - Herbaceous (3-15 ft)
Form & Appearance
Habit / form
Erect
Leaf color
Green
Leaf type
Compound (Pinnately , Bipinnately, Palmately)
Leaf arrangement
Alternate
Leaf margin
Entire; Lobed
Hairs present
No
Leaf detail
Leaves alternate, long-stalked, palmately divided or lobed.
Flower color
Blue; Pink; Purple/Lavender; White
Flower value
Good Cut; Showy
Flower form
Panicle; Raceme
Flower detail
Flowers bloom from May to mid-Summer in terminal, elongated clusters, blue to purple or nearly white, with a single spur on the back side.
Bloom time
Spring; Summer
Fruit color
Black; Brown/Copper
Fruit detail
Fruit dry, many seeded.
Wildlife & Ecology
Native status
Native
Origin
Temperate and Subtropical Old World, North America
Distribution
Throughout Europe, Asia, North and Central Africa, North and Central America.
Wildlife value
Attracts hummingbirds and butterflies.
Attracts
Butterflies; Hummingbirds
Food & Medicine

Edibility

Poisonous. Plants are considered toxic to humans if ingested.

Landscape Use
Landscape location
Meadow; Naturalized Area; Woodland
Landscape theme
Cottage Garden
Design feature
Border; Mass Planting
Garden tags
#poisonous #purple #drought tolerant #NC native #spring interest #pink flowers #problem for dogs #problem for horses #problem for cats #full sun tolerant #partial shade tolerant #white flowers #perennial #annual #HS304
Problems & Resistance
Problems
Poisonous to Humans; Problem for Cats; Problem for Dogs; Problem for Horses; Weedy
Resistant to
Deer; Drought; Rabbits
Particularly resistant to
Drought tolerant
Propagation
Seed
Poison severity
High
Poison parts
Flowers; Leaves; Seeds; Stems
Poison symptoms
Burning of lips and mouth, numbness of throat; intense vomiting and diarrhea, muscular weakness and spasms, weak pulse, paralysis of the respiratory system, convulsions. Can cause serious illness or death. Unless there is a lack of suitable forage, horses typically do not consume toxic amounts of larkspur. The toxicity of the plant may vary depending on seasonal changes and field conditions; as the plant matures, it generally becomes less toxic. Clinical effects include constipation, colic, increased salivation, stiffness, recumbency, and convulsions. Cardiac failure may occur, as can death from respiratory paralysis.
Toxic principle
Alkaloids delphinine, ajacine, and others.
Contact dermatitis
No
Toxicity summary
High severity poison; parts: Flowers; Leaves; Seeds; Stems

Planted at Hunnicutt

Nobody’s planted this one yet.