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Allium ‘Firmament’ (Ornamental Onion)

Ornamental Onion 'Firmament', Ornamental Garlic 'Firmament', Spring Bulbs, Spring Flowers

Allium 'Firmament', Ornamental Onion 'Firmament', Ornamental Garlic 'Firmament', Spring Bulbs, Spring Flowers,Giant Onions, Purple flowers
Allium 'Firmament', Ornamental Onion 'Firmament', Ornamental Garlic 'Firmament', Spring Bulbs, Spring Flowers,Giant Onions, Purple flowers
Allium 'Firmament', Ornamental Onion 'Firmament', Ornamental Garlic 'Firmament', Spring Bulbs, Spring Flowers,Giant Onions, Purple flowers

Regarded by some as one of the very best, Allium ‘Firmament’ is a rather unusual Allium. Instead of having round flowerheads, it is only two-thirds of the sphere, about 4-5 in. wide (10-12 cm). It is packed with star-shaped, dark silvery purple flowers, each flower being comprised of dark purple florets adorned with shimmering silver anthers. Blooming from late spring to early summer, this striking bulbous perennial enjoys a long-lasting season of interest and remains ornamental in the garden well into summer. A lovely cross between Allium christophii and Allium atropurpureum.

  • Growing up to 24-30 in. tall (60-75 cm), this beauty 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.

Requirements

Hardiness 5 - 8
Climate Zones 1, 1A, 1B, 2, 2A, 2B, 3, 3A, 3B, 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 Amaryllidaceae
Genus Allium
Common names Ornamental Onion, Onion
Exposure Full Sun
Season of Interest Spring (Late)
Summer (Early)
Height 2' - 3'
(60cm - 90cm)
Spread 1' - 2'
(30cm - 60cm)
Spacing 8" (20cm)
Depth 8" (20cm)
Maintenance Low
Water Needs Average
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, Showy
Tolerance Drought, Deer, Rabbit
Attracts Bees, Butterflies
Garden Uses Beds And Borders
Garden Styles Informal and Cottage, Formal Garden
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Do I Need?
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Alternative Plants to Consider

Allium cepa Aggregatum Group (Shallot)
Allium cepa (Onion)
Allium sativum (Garlic)
Allium amethystinum ‘Red Mohican’ (Ornamental Onion)
Allium ‘Purple Rain’ (Ornamental Onion)
Allium ‘Pinball Wizard’ (Ornamental Onion)

Recommended Companion Plants

Eryngium bourgatii ‘Picos Blue’ (Mediterranean Sea Holly)
Anthriscus sylvestris ‘Ravenswing’ (Cow Parsley)
Gladiolus communis subsp. byzantinus (Byzantine Gladiolus)
Stipa tenuissima (Mexican Feather Grass)

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Allium (Ornamental Onion)
Great Rose Companion Plants: Allium
Bulbs that return to the garden year after year!
Tall Alliums for your Garden Borders
Small Allium Species for the Rock Garden
Learn How To Plant And Care for Your Spring Flower Bulbs
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Awesome Allium Combos
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.
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Requirements

Hardiness 5 - 8
Climate Zones 1, 1A, 1B, 2, 2A, 2B, 3, 3A, 3B, 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 Amaryllidaceae
Genus Allium
Common names Ornamental Onion, Onion
Exposure Full Sun
Season of Interest Spring (Late)
Summer (Early)
Height 2' - 3'
(60cm - 90cm)
Spread 1' - 2'
(30cm - 60cm)
Spacing 8" (20cm)
Depth 8" (20cm)
Maintenance Low
Water Needs Average
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, Showy
Tolerance Drought, Deer, Rabbit
Attracts Bees, Butterflies
Garden Uses Beds And Borders
Garden Styles Informal and Cottage, Formal Garden
How Many Plants
Do I Need?
Explore Great Plant Combination Ideas
Allium
Guides with
Allium
Not sure which Allium to pick?
Compare Now

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