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Giganteum Ornamental Onion

Allium 'Giganteum'

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Overview

Allium 'Giganteum', or Giant Ornamental Onion, adds dramatic flair with its lofty stems rising up to 5 feet tall. Each spherical bloom clusters, roughly 6-8 inches in diameter, boast countless star-shaped purple flowers. These low-maintenance perennials thrive in full sun to part shade and prefer well-drained soil. Flowering in late spring to early summer, they also provide striking vertical interest and are excellent for attracting pollinators. Hardy in zones 6-10.

Sun Full, HalfWater MediumZones 4–8Climate Temperate
Giganteum Ornamental Onion (Allium 'Giganteum') — or Giant Ornamental Onion

Culture

Sun
Full, Half
Water
Medium
USDA zones
4–8

Shape & size

Mature height
4–5 Ft.

Classification

Family
Liliaceae
Climate
Temperate

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Photos (63)

Giganteum Ornamental Onion (Allium 'Giganteum') — lavender flowers in the garden; is a striking and statuesque bulbous perennial renowned for its impressive
Giganteum Ornamental Onion (Allium 'Giganteum') — bulb for full or half; potentially providing an increased presence in the landscape over time
Giganteum Ornamental Onion (Allium 'Giganteum') — or Giant Ornamental Onion; these low-maintenance perennials thrive in full sun to part shade and, image 51
Giganteum Ornamental Onion (Allium 'Giganteum') — Flowering in late spring to early summer; commonly known as Giganteum Ornamental Onion, image 55
Giganteum Ornamental Onion (Allium 'Giganteum') — These low-maintenance perennials thrive in full sun to part shade and prefer well-drained soil, image 54
Giganteum Ornamental Onion (Allium 'Giganteum') — Each spherical bloom clusters, roughly 6-8 inches in diameter, boast countless star-shaped purple, image 53
Giganteum Ornamental Onion (Allium 'Giganteum') — adds dramatic flair with its lofty stems rising up to 5 feet tall; deep lilac flowers that create, image 52
Giganteum Ornamental Onion (Allium 'Giganteum') — they also provide striking vertical interest and are excellent for attracting pollinators; it is, image 56
Giganteum Ornamental Onion (Allium 'Giganteum') — commonly known as Giganteum Ornamental Onion; allium 'Giganteum' can naturalize by self-seeding, image 57
Giganteum Ornamental Onion (Allium 'Giganteum') — Regarded as one of the tallest and most architectural onions in its genus; this plant typically, image 59
Giganteum Ornamental Onion (Allium 'Giganteum') — is a striking and statuesque bulbous perennial renowned for its impressive spherical blooms; each, image 58
Giganteum Ornamental Onion (Allium 'Giganteum') — rising majestically above clumps of gray-green, image 63
Giganteum Ornamental Onion (Allium 'Giganteum') — These spherical umbels appear in late spring to early summer; they also provide striking vertical, image 62
Giganteum Ornamental Onion (Allium 'Giganteum') — deep lilac flowers that create a dramatic focal point in any garden; bulb with lavender blooms, image 61
Giganteum Ornamental Onion (Allium 'Giganteum') — this plant typically reaches heights of 3 to 5 feet; the Giganteum Ornamental Onion also attracts, image 60

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