Alphabetical Plant Listing

Allium nigrum (Ornamental Onion)

Flowering Onion, Black Garlic, Allium Multibulbosum, Black Garlic, Broad-Leaved Onion, Spring Bulbs, Spring Flowers


Despite its name, Allium nigrum is a white flowering onion, featuring creamy-white or pale lilac flat clusters, about 3-4 inch wide (8-10 cm), of starry silvery florets with a green center. Blooming in late spring to early summer, this hardy perennial bulb enjoys is a beautiful addition to the perennial garden and is also an excellent cut flower.

  • Growing up to 18 - 24 in. high (45 - 60 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. Add grit when grown in clay soils to improve drainage. 
  • Known for attracting bees, butterflies, ​moths, and other pollinators, but deer ignore it.
  • Stunning in beds and borders, city gardens, cottage gardens, and gravel 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.
  • No serious pest or disease issues. Keep an eye out for onion rot and downy mildew.
  • Propagate by seed, sowing in containers in a cold frame when just ripe or in the spring. Alternatively, remove offsets in autumn.
  • Allium nigrum is native to the Middle East.

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.

Read More

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Requirements

Hardiness 4 – 9
Heat Zones 1 – 9
Plant Type Bulbs
Plant Family Allium
Exposure Full Sun
Season of Interest Spring (Late)
Summer (Early)
Height 1' – 2' (30cm – 60cm)
Spread 1' – 2' (30cm – 60cm)
Spacing 6" (15cm)
Depth 6" (15cm)
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, Fragrant, Showy
Tolerance Deer, Rabbit
Attracts Butterflies
Garden Uses Beds and Borders
Garden Styles City and Courtyard, Informal and Cottage

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Great Plant Combination Ideas with Allium

Guides with Allium


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 4 – 9
Heat Zones 1 – 9
Plant Type Bulbs
Plant Family Allium
Exposure Full Sun
Season of Interest Spring (Late)
Summer (Early)
Height 1' – 2' (30cm – 60cm)
Spread 1' – 2' (30cm – 60cm)
Spacing 6" (15cm)
Depth 6" (15cm)
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, Fragrant, Showy
Tolerance Deer, Rabbit
Attracts Butterflies
Garden Uses Beds and Borders
Garden Styles City and Courtyard, Informal and Cottage

Great Plant Combination Ideas with Allium

Guides with Allium

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