Vernonia missurica - ​Dark purple flowers en masse top erect stems that may grow to 4 feet. Missouri Ironweed is one of the shorter growers among this under-appreciated clan in Asteraceae. Just perfect with late season Rudbeckia, Aclepias, Helianthus as well as Eupatorium. Average to fertile, moisture-retentive soil in plenty of sun will satisfy its needs. Middle of the border, meadow, the perennial garden with an emphasis on late season flowering plants. Established potted Ironweed from cutting or division.