Ornamental Onion Allium caeruleum
Other plants called Ornamental Onion:
Previously known as:
- Allium azureum
- Phonetic Spelling
- AL-ee-um seh-ROO-lee-um
- This plant has low severity poison characteristics.
- See below
- Description
-
Ornamental Onion is a bulb native to Asia with clear blue flowers in 1-inch clusters above 20- 24 inch naked stems in May-June. The leaves clasp the lower stem but often disappear by blooming time. They spread by bulblets and self-seeding. Plant bulbs 6 inches deep in the fall for spring blooms. They tolerate summer drought but require moisture during the growing season. Deer, rabbits and voles tend to avoid the plants. They can be weedy in the garden and disturbed areas so deadhead to prevent self-seeding.
Plant in humus-rich well-drained moist to dry loams in full sun for best blooming. Use in perennial beds, rock gardens, meadows, cottage garden, and naturalized areas. Also good as a cut flower.
VIDEO Created by Elisabeth Meyer for "Annuals, Perennials, Vines, and Groundcovers" a plant identification course offered in partnership with Longwood Gardens.
- Profile Video:
- See this plant in the following landscape:
- Floricyle
- Cultivars / Varieties:
-
- 'Blue Drumstick'
Darker blue flower - ‘Heacock Form’
Larger blue inflorescence
- 'Blue Drumstick'
- 'Blue Drumstick', ‘Heacock Form’
- Tags:
- Cultivars / Varieties:
-
- 'Blue Drumstick'
Darker blue flower - ‘Heacock Form’
Larger blue inflorescence
- 'Blue Drumstick'
- 'Blue Drumstick', ‘Heacock Form’
- Tags:
-
-
Attributes:
- Genus:
- Allium
- Species:
- caeruleum
- Family:
- Alliaceae
- Life Cycle:
- Bulb
- Perennial
- Recommended Propagation Strategy:
- Division
- Country Or Region Of Origin:
- Central Asia
- Particularly Resistant To (Insects/Diseases/Other Problems):
- Drought, normally not susceptible to animals
- Edibility:
- Flowers have a mildly bitter flavor and like young leaves can be eaten in small quantities raw in salads and sandwiches or cooked in tea and soups. However, the plant also has poisonous characteristics as noted in the "Poisonous to Humans" section of this record. Toxicity can depend on the age of the person or animal, the age of the plant, the part of the plant ingested, how much is ingested, whether the person or animal has sensitivities or allergies, whether it's eaten raw or cooked, and so forth. Consult with a medical professional for further details.
- Dimensions:
- Height: 1 ft. 0 in. - 2 ft. 0 in.
- Width: 0 ft. 6 in. - 1 ft. 0 in.
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-
Whole Plant Traits:
- Plant Type:
- Bulb
- Perennial
- Poisonous
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Cultural Conditions:
- Light:
- Full sun (6 or more hours of direct sunlight a day)
- Soil Texture:
- High Organic Matter
- Loam (Silt)
- Sand
- Soil Drainage:
- Good Drainage
- Moist
- Occasionally Dry
- Available Space To Plant:
- Less than 12 inches
- NC Region:
- Coastal
- Mountains
- Piedmont
- USDA Plant Hardiness Zone:
- 4a, 4b, 5a, 5b, 6a, 6b, 7a, 7b, 8a, 8b
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Fruit:
- Fruit Type:
- Capsule
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Flowers:
- Flower Color:
- Blue
- Flower Inflorescence:
- Umbel
- Flower Value To Gardener:
- Fragrant
- Good Cut
- Flower Bloom Time:
- Spring
- Flower Shape:
- Star
- Flower Petals:
- 6 petals/rays
- Flower Size:
- < 1 inch
- Flower Description:
- Flowers are small, 6-parted, in a 1-inch cluster at the top of a 20-24 inch naked stem. Blooms late spring in May-June
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Leaves:
- Leaf Color:
- Green
- Leaf Type:
- Simple
- Leaf Arrangement:
- Alternate
- Leaf Shape:
- Linear
- Leaf Margin:
- Entire
- Hairs Present:
- No
- Leaf Length:
- > 6 inches
- Leaf Width:
- < 1 inch
- Leaf Description:
- Linear green leaves huge the lower stem and often are gone by bloom time.
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-
Stem:
- Stem Color:
- Green
- Stem Is Aromatic:
- No
- Stem Cross Section:
- Round
- Stem Form:
- Straight
- Stem Surface:
- Smooth (glabrous)
- Stem Description:
- Tall naked smooth green stem
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-
Landscape:
- Landscape Location:
- Meadow
- Landscape Theme:
- Cottage Garden
- Rock Garden
- Attracts:
- Bees
- Butterflies
- Resistance To Challenges:
- Drought
- Problems:
- Weedy
