Allegheny Onion Allium cernuum
Other Common Name(s):
- Phonetic Spelling
- AL-ee-um SAIR-new-um
- Description
-
Nodding onion is a North American native perennial bulb in the onion family (Amaryllidaceae) that is found in open woodlands and around shale outcrops in the low elevation mountains. This plant grows 1 to 2 feet tall with long grass-like foliage. The genus name comes from Latin meaning garlic and the species name means nodding.
Nodding onion prefers well-drained, humus-rich, alkaline or neutral soil in full sun. It is drought-tolerant once established and easy to grow. Nodding clusters of bell-shaped, pink or white flowers bloom in June to August and are attractive to pollinators and songbirds. It will spread by both bulb offsets and seeds but is easiest to propagate by dividing the bulblets.
All parts of the plant have an oniony smell. It was once used in cooking but it is mainly used for its flowers now.
It can be used in rock, culinary, cottage, butterfly, native or pollinator gardens. It may be mass planted or used in small groups within borders. It will also naturalize in a meadow or open woodland setting.
Insects, Diseases, and Other Plant Problems: No significant problems.
VIDEO Created by Elisabeth Meyer for "Edibles, Bulbs, and Houseplants" a plant identification course offered in partnership with Longwood Gardens.
- Profile Video:
- See this plant in the following landscape:
- Cultivars / Varieties:
-
- Tags:
- Cultivars / Varieties:
-
- Tags:
-
-
Attributes:
- Genus:
- Allium
- Species:
- cernuum
- Family:
- Amaryllidaceae
- Life Cycle:
- Bulb
- Perennial
- Recommended Propagation Strategy:
- Division
- Seed
- Country Or Region Of Origin:
- North America
- Distribution:
- AL , AR , AZ , CO , DC , GA , IA , ID , IL , IN , KY , MD , MI , MN , MO , MS , MT , NC , NE , NJ , NM , NY , OH , OR , PA , SC , SD , TN , TX , UT , VA , WA , WI , WV , WY
- Wildlife Value:
- Pollinators and songbirds are attracted to the plant.
- Edibility:
- The bulb is edible but is rarely used as better plants exist for this purpose.
- Dimensions:
- Height: 0 ft. 6 in. - 2 ft. 0 in.
- Width: 0 ft. 4 in. - 1 ft. 0 in.
-
-
Whole Plant Traits:
- Plant Type:
- Bulb
- Herbaceous Perennial
- Native Plant
- Wildflower
- Habit/Form:
- Arching
- Erect
- Growth Rate:
- Medium
- Maintenance:
- Low
- Texture:
- Fine
-
-
Cultural Conditions:
- Light:
- Full sun (6 or more hours of direct sunlight a day)
- Partial Shade (Direct sunlight only part of the day, 2-6 hours)
- Soil Texture:
- High Organic Matter
- Soil pH:
- Alkaline (>8.0)
- Neutral (6.0-8.0)
- Soil Drainage:
- Good Drainage
- Moist
- Occasionally Dry
- Available Space To Plant:
- Less than 12 inches
- NC Region:
- Mountains
- Piedmont
- USDA Plant Hardiness Zone:
- 4a, 4b, 5a, 6a, 6b, 7a, 7b, 8a, 8b
-
-
Fruit:
- Fruit Color:
- Black
- Display/Harvest Time:
- Fall
- Summer
- Fruit Type:
- Capsule
- Fruit Length:
- < 1 inch
- Fruit Width:
- < 1 inch
- Fruit Description:
- Spherical crested fruits that split open to expel shiny black seeds. Fruit displays from August to October.
-
-
Flowers:
- Flower Color:
- Pink
- Purple/Lavender
- White
- Flower Inflorescence:
- Umbel
- Flower Value To Gardener:
- Fragrant
- Showy
- Flower Bloom Time:
- Summer
- Flower Shape:
- Bell
- Flower Petals:
- 6 petals/rays
- Flower Size:
- < 1 inch
- Flower Description:
- Pink, lavender or white bell-shaped fragrant flowers bloom from June to August in 1.5 to 2-inch clusters. Individual flowers are 1/4 inch wide with 6 tepals and yellow stamens.
-
-
Leaves:
- Leaf Color:
- Green
- Leaf Value To Gardener:
- Fragrant
- Leaf Type:
- Simple
- Leaf Arrangement:
- Rosulate
- Leaf Shape:
- Linear
- Leaf Margin:
- Entire
- Hairs Present:
- No
- Leaf Length:
- > 6 inches
- Leaf Width:
- < 1 inch
- Leaf Description:
- Linear basal flat green leaves are up to 12 inches long and erect to arching. Margins are smooth, venation is parallel.
-
-
Stem:
- Stem Color:
- Green
- Red/Burgundy
- Stem Is Aromatic:
- No
- Stem Cross Section:
- Round
- Stem Form:
- Straight
- Stem Surface:
- Smooth (glabrous)
- Stem Description:
- Light green to reddish-green smooth round stems
-
-
Landscape:
- Landscape Location:
- Meadow
- Naturalized Area
- Small Space
- Walkways
- Woodland
- Landscape Theme:
- Butterfly Garden
- Cottage Garden
- Native Garden
- Pollinator Garden
- Design Feature:
- Border
- Mass Planting
- Small groups
- Attracts:
- Bees
- Butterflies
- Hummingbirds
- Pollinators
- Songbirds
- Resistance To Challenges:
- Black Walnut
- Drought
- Poor Soil
