Allium giganteum (Ornamental Onion)
Ornamental Onion, Ornamental Garlic, Giant Onion, Giant Allium, Spring Bulbs, Spring Flowers
Perhaps the tallest of the ornamental onions, Allium giganteum is a bold and striking addition to the garden with its star-shaped, tiny lilac-purple flowers forming a 5-6 in. wide (12-15 cm) globe-shaped cluster. Blooming in late spring to early summer, this Giant Allium enjoys long-lasting blooms and remains ornamental in the garden well into summer. This bulbous perennial makes a perfect background plant that you may want to combine with finer-textured plants such as ornamental grasses. Great in fresh or dried flower arrangements too!
- Recipient of the prestigious Award of Garden Merit by the Royal Horticultural Society
- Grows up to 5-6 ft. tall (150-180 cm). Allium giganteum naturalizes easily and will come back year after year!
- Easily grown in rich, sandy to gritty, dry to medium moisture, well-drained soils in full sun. This Allium is drought tolerant.
- Known for attracting bees, butterflies, moths, and other pollinators, but deer ignore it.
- Stunning in beds, borders, and cottage gardens. Spectacular in large sweeping drifts. Plant in groups (at least 10 to 15 bulbs) for the best visual impact. Excellent as cut flowers for both fresh and dried arrangements!
- Mixes beautifully with other late spring flowering bulbs and creates stunning combinations with pink or white delphiniums, peonies, or irises.
- To be planted in fall.
Hundreds of Allium species exist, but only a few have made a name for themselves as garden plants. The ornamental onions distinguish themselves by their remarkable diversity in color, inflorescence, and flowering height. Many species bloom in early summer - just after the spring-flowering period and just before the exuberant full bloom of summer. Certain small species are just perfect for a rock garden, and several lend themselves to naturalizing. All species can be used in the border.
Learn How To Plant And Care for Your Spring Flower Bulbs
To achieve optimum flowering results, it is important to plant the bulbs at the right time.
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Requirements
Hardiness | 6
– 10 |
---|---|
Heat Zones | 5
– 9 |
Climate Zones | 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24 |
Plant Type | Bulbs |
Plant Family | Allium |
Exposure | Full Sun |
Season of Interest |
Spring (Late) Summer (Early) |
Height | 5' – 6' (150cm – 180cm) |
Spread | 1' – 2' (30cm – 60cm) |
Spacing | 8" (20cm) |
Depth | 8" (20cm) |
Water Needs | Average |
Maintenance | Low |
Soil Type | Chalk, Clay, Loam, Sand |
Soil pH | Acid, Alkaline, Neutral |
Soil Drainage | Moist but Well-Drained, Well-Drained |
Characteristics | Dried Arrangements, Cut Flowers, Fragrant, Plant of Merit, Showy |
Tolerance | Deer, Drought, Rabbit |
Attracts | Bees, Butterflies |
Garden Uses | Beds and Borders |
Garden Styles | Formal Garden, Informal and Cottage |
©Clive Nichols
While every effort has been made to describe these plants accurately, please keep in mind that height, bloom time, and color may differ in various climates. The description of these plants has been written based on numerous outside resources.
Requirements
Hardiness | 6
– 10 |
---|---|
Heat Zones | 5
– 9 |
Climate Zones | 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24 |
Plant Type | Bulbs |
Plant Family | Allium |
Exposure | Full Sun |
Season of Interest |
Spring (Late) Summer (Early) |
Height | 5' – 6' (150cm – 180cm) |
Spread | 1' – 2' (30cm – 60cm) |
Spacing | 8" (20cm) |
Depth | 8" (20cm) |
Water Needs | Average |
Maintenance | Low |
Soil Type | Chalk, Clay, Loam, Sand |
Soil pH | Acid, Alkaline, Neutral |
Soil Drainage | Moist but Well-Drained, Well-Drained |
Characteristics | Dried Arrangements, Cut Flowers, Fragrant, Plant of Merit, Showy |
Tolerance | Deer, Drought, Rabbit |
Attracts | Bees, Butterflies |
Garden Uses | Beds and Borders |
Garden Styles | Formal Garden, Informal and Cottage |