Giant Ironweed, PA Ecotype

Vernonia gigantea (Giant Ironweed) is an erect-growing, clump-forming native that typically grows to 9.8 ft. Giant Ironweed blooms in late summer/early fall with purple flowers that attract butterflies. Giant Ironweed’s lance-shaped leaves grow in an alternate arrangement on the stem. Vernonia gigantea may be distinguished from Vernonia noveboracensis by the absence of hair-like extensions on the phyllaries (leaf bracts). Giant Ironweed grows in mesic to wet soils of floodplains, wet woods, and meadows. Vernonia gigantea occurs from New York to Florida and Nebraska to Texas. Giant Ironweed is deer resistant. Vernonia gigantea is very susceptible to leaf rusts and mildew. For this reason, Giant Ironweed is best used in mixes and not monocultures. We use Vernonia gigantea in pollinator-friendly riparian, wet meadow, and wetland seed mixes. Vernonia gigantea is a member of the Aster (Asteraceae) family. The genus name Vernonia honors English botanist William Vernon. The species name gigantea means unusually tall or large.