Giant Ironweed
Vernonia gigantea
Found in pastures, bottomlands, streamsides, moist thickets, roadsides, disturbed wet or dry sands. Weakley, Flora of the Southeastern United States (2025), South Central edition What its natural habitat tells you
Native to Mississippi (estimated). How scores work Is it native here?
Profile 94%
- Height
- 3–12 feet
- Spread
- 3–6 feet
- Light
- Full sun, Partial shade
- Soil moisture
- Usually moist
Space about 4.5 ft apart from its recorded spread, about 5 per 100 sq ft. Enter your bed size for a count
Will it fit your yard?No photograph yet. Looking for an old drawing…
At a glance
- Life cycle
- Perennial
- Leaves
- Deciduous
- Bloom
- August to October
- Fruiting season
- August to November
Recorded in 66 Mississippi counties.
Natural habitats
Places it grows wild. Not a planting requirement. Each habitat page lists the plants and wildlife also found there.

Roadsides, fields and disturbed ground
Ground opened by people: roadsides, old fields, pastures, fencerows and lots.
Floodplain and bottomland forests
Forests on low ground beside rivers and streams that flood from time to time.
Streams, rivers and their banks
Flowing water and its banks, bars and rocky shoals.
Who uses this plant?
24CaterpillarsGenus host records with ranges including MS
Genus host records with ranges including MS · Vernonia
- Acleris subnivanaBent-Wing Acleris, Common Acleris
- Anavitrinella pampinariaCommon Gray, Cranberry Spanworm
- Apantesis partheniceParthenice Tiger Moth
- Archips rileyanaSouthern Ugly-Nest Caterpillar Moth
- Carmenta bassiformisEupatorium Borer Moth, Ironweed Clearwing Moth
- Chlorochlamys chloroleucariaBlackberry Looper Moth
- Dichomeris setosellaHairy Dichomeris
- Estigmene acreaSalt Marsh Moth, Acrea Moth
- Eupithecia miserulataCommon Eupithacia, Common Pug
- Hellinsia paleaceusOne-Spotted Plume Moth
Show all 24
- Papaipema baptisiaeWild Indigo Borer, Indigo Stem Borer
- Papaipema cerussataIronweed Borer Moth
- Perigea xanthioidesRed Groundling
- Platynota idaeusalisTufted Apple-Bud Moth
- Pleuroprucha insulsariaCommon Tan Wave
- Polygrammodes flavidalisIronweed Root Moth, Vernonia Root-Borer
- Spodoptera ornithogalliYellow-Striped Armyworm Moth, Cotton Cutworm
- Synchlora aerataWavy-Lined Emerald, Camouflaged Looper
- Synchlora frondariaSouthern Emerald
- Thyridopteryx ephemeraeformisEvergreen Bagworm Moth
- Vanessa virginiensisAmerican Lady, American Painted Lady
- Paralobesia sambuci
- Paralobesia vernoniana
- Thyraylia bunteana
46BeesSoutheastern regional records
Southeastern regional records · Vernonia
Individual names are not available yet.
Noori, Seltmann & Orr 2026, A curated and integrated dataset for exploring global bee-plant interactions (GloBI), Zenodo, CC BY 4.0
9Specialist beesPollen specialists
Pollen specialists · Vernonia
- Andrena placata
- Melissodes denticulatus
- Melissodes druriellus
- Melissodes microstictus
- Melissodes niveus
- Melissodes subillatus
- Melissodes trinodis
- Melissodes vernoniae
- Perdita octomaculata
No records yet · Ants · Beetles · Flies · Adult butterflies / moths · Other wasps · Other insects
Plant details
- Family
- Asteraceae
- Hardiness
- Zones 5a–8b
- Soil pH
- Acidic to alkaline
- Flower color
- Purple
- Fruit begins
- August
- Fruit ends
- November
Safety has not been reviewed for this plant; check toxicity and thorns before planting.
Growing sources and scope
- Bloom · “Late August to October” · Weakley, Flora of the Southeastern United States (2025), Carolinas & Georgia edition (ranked first; Prairie Moon 2026 Cultural Guide differs) · Carolinas and Georgia
- Flower color · “Purple” · NC Extension Plant Toolbox
- Fruit begins · “August” · Weakley, Flora of the Southeastern United States (2025), Carolinas & Georgia edition · Carolinas and Georgia
- Fruit ends · “November” · Weakley, Flora of the Southeastern United States (2025), Carolinas & Georgia edition · Carolinas and Georgia
- Hardiness · “Zones 5a–8b” · NC Extension Plant Toolbox
- Height · “3–12 feet” · NC Extension Plant Toolbox (ranked first; Prairie Moon 2026 Cultural Guide differs)
- Leaves · “Deciduous” · NC Extension Plant Toolbox
- Life cycle · “Perennial” · NC Extension Plant Toolbox
- Light · “Full sun (6 or more hours of direct sunlight a day); Partial shade (direct sunlight only part of the day, 2-6 hours)” · NC Extension Plant Toolbox (ranked first; Prairie Moon 2026 Cultural Guide differs)
- primary_flower_color · “purple” · Prairie Moon 2026 Cultural Guide
- Soil · “Moist” · NC Extension Plant Toolbox (ranked first; Prairie Moon 2026 Cultural Guide differs)
- Soil pH · “Acidic to alkaline” · NC Extension Plant Toolbox
- Spread · “3–6 feet” · NC Extension Plant Toolbox
Conservation status
| Mississippi rank | SNR |
|---|---|
| Global rank | G5 |
| MS status | Not verified |
| Federal status | Not verified |
Will it fit your yard?
Check this plant against your county, sun and soil moisture. Conditions are checked in your browser.
Sources
- Weakley, Flora of the Southeastern United States (2025), South Central edition
- USDA PLANTS
- Vascular Plants of North Carolina (NC Natural Heritage Program)
- Mississippi occurrence source
- Shropshire & Tallamy 2025, Lepidoptera of North America north of Mexico, ZooKeys 1261 (ODbL)
- Noori, Seltmann & Orr 2026, A curated and integrated dataset for exploring global bee-plant interactions (GloBI), Zenodo, CC BY 4.0
- Smith, Bachelder, Russell, Morales, Mosher & Seltmann 2024, Bee-Specialization-Modeling v0.6.1 (specialist host table compiled from J. Fowler's pollen specialist bee lists), Zenodo, CC BY 4.0
- Hurlbert, Olsen, Sawyer & Winner 2021, Avian Diet Database, Scientific Data 8: 260 (CC0)
- Narango, Tallamy & Shropshire 2020, Few keystone plant genera support the majority of Lepidoptera species, Nature Communications

