Swamp Onion

Allium madidum

Native to:
United States

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Taxonomy

Division:
Magnoliophyta | - Flowering plants
Family:
Amaryllidaceae
Genus:
Allium
Species:
Allium madidum
USDA Symbol:
ALMA6

Growth Characteristics

Life Cycle:
Perennial
Growth Habit:
Geophyte
Height:
40 cm
Light Requirements:
Full Sun
Drought Tolerance:
Low
Bloom Months:
may,jun,jul
Bloom Colors:
pink, purple

Wildlife Benefits

Bees:
★☆☆☆☆ Documented bee visitation (GBIF)
Butterflies & Moths:
★☆☆☆☆ Documented Lepidoptera association (GBIF)

Reported Fauna Sightings

Bees: Two-form bumble bee (Bombus bifarius)

Garden & Ecology Notes

Wildlife Value:
bees, butterflies
Deer Resistant:
Yes
Fragrant:
Yes

Soil Requirements

Soil Type:
moist, fertile, well-drained loam
pH:
5.5 - 7.0 (slightly acidic to neutral)
Drainage:
excellent drainage required
Moisture:
consistently moist
Notes:
prefers habitats near streams or wetlands

Propagation & Germination

Stratification:
Cold/moist stratification required — 60–90 days
Germination Time:
14–30 days
Notes:
Seeds germinate best with cold-moist stratification and consistent moisture. Light may enhance germination.