Missouri ironweed is a perennial plant that is native to the north-eastern parts of the US where it grows in locations that are consistently moist and light. It bears bright purple one-inch flowers in late summer to mid-fall providing a pop of color in the late season and has long lance-shaped leaves. In trials at the Chicago Botanic Garden this ironweed grew to a height or about six feet and width of about five feet in sunny conditions and received a good rating for growing locally.