Giant Ironweed
Vernonia gigantea
- Native to:
- Canada, United States, Virgin Islands
Greg Hume
Taxonomy
- Division:
- Magnoliophyta | - Flowering plants
- Family:
- Asteraceae
- Genus:
- Vernonia
- Species:
- Vernonia gigantea
- USDA Symbol:
- VEGI
Growth Characteristics
- Life Cycle:
- Perennial
- Growth Habit:
- Forb/herb
- Height:
- 300 cm
- Light Requirements:
- Full Sun,Part Shade,Shade
- Drought Tolerance:
- Medium
- Bloom Months:
- aug,sep,oct
- Bloom Colors:
- purple
Wildlife Benefits
- Bees:
- ★★☆☆☆ Documented bee visitation (GBIF)
- Butterflies & Moths:
- ★★★☆☆ Documented Lepidoptera association (GBIF)
- Hummingbirds:
- ★☆☆☆☆ Documented hummingbird visits (GBIF)
Keystone Species Ranking
- Pollen Specialist Bee Keystone:
- ★★☆☆☆ Native pollen specialist bee species supported by this genus (NWF)
Reported Fauna Sightings
Bees: American bumble (Bombus pensylvanicus) Hummingbirds: Ruby-throated Hummingbird (Archilochus colubris) Butterflies:Eastern Tiger Swallowtail (Papilio glaucus), Silver-spotted Skipper (Epargyreus clarus)
Garden & Ecology Notes
- Wildlife Value:
- butterflies, bees, birds
Soil Requirements
- Soil Type:
- rich, well-drained loamy soil
- pH:
- 5.5 - 7.0 (slightly acidic to neutral)
- Drainage:
- tolerates poor drainage
- Moisture:
- consistently moist
- Notes:
- prefers fertile, organic-rich environments
Propagation & Germination
- Stratification:
- Cold/moist stratification required — 30–60 days
- Germination Time:
- 14–30 days
- Notes:
- Seeds germinate readily after cold stratification; surface sow and keep moist.
Where to Buy
Nationwide Seller
- Sheffield's Seed (seeds)
- Ernst Seeds (seeds)
- Prairie Moon Nursery (nursery and seeds)
- Native Plants Nursery (nursery)