Delphinium Grand. Summer Nights

Summer Night delphinium

Delphinium grandiflorum ‘Summer Nights’ is a compact, clump-forming perennial valued for its upright to slightly spreading form and rich deep violet-blue flowers that bloom over an extended period from late spring into summer, creating a vibrant display, with finely divided green foliage that may yellow and die back after flowering.


Mature Size:
Width: 12–18 in
Height: 12–18 in

USDA Zones: 3a–7b (best performance in cooler climates; more heat tolerant than tall delphiniums)
Light: Full sun to partial shade
Blooms: Deep violet-blue flowers from late spring into summer
Soil: Well-drained, moderately fertile soil
Water: Moderate; prefers consistent moisture


🌸 Landscape Uses
Perennial borders, edging, containers, rock gardens, mass plantings


🌼 Attracts & Tolerances
Attracts: Pollinators
Tolerances: Deer resistant, moderate heat tolerance

Plant type

Perennial

Height

12-18''

Width

12-18"

Hardiness zones

3–7

Sunlight

Full Sun, Partial Shade

Bloom time

Late Spring, Spring

Flower color

Blue

Leaf color

Green

Fall color

Green

Attracts

Butterflies, Hummingbirds

Soil

Loamy, Well Drained

Landscape use

Border, Mass Planting

Shape

Clump, Compact

Fragrant

Yes

Drought tolerant

No