Giant ironweed is a perennial plant that is native to the eastern parts
of the US where it grows in locations that are consistently moist. It
bears smallish bright purple flowers large bracts in late summer to
mid-fall providing an unusual pop of tall color in the late season.
Giant ironweed grows to a height of about eight feet and a width of
about seven feet in sunny conditions, and slightly less in shadier spots.
It can become weedy, so care should be taken in siting it, and removing
unwanted shoots. In an evaluation of ironweeds conducted at the Chicago
Botanic Garden, this form of giant ironweed received a good rating for growing
in local conditions. This particular ironweed shares its common name with Vernonia gigantea so before purchasing it is advisable to check the correct botanical name.