True to its name, this perennial is tough as iron! In late summer, clusters of rosy purple flowers will begin to cover the top half of the plant. Dark olive green foliage has a silver cast, adding interest through the rest of the year. 'Prairie Princess' is more compact, has a fuller habit, and sturdy stems that avoid opening up in heavy rains or under the weight of bloom. This variety was also selected for holding its foliage all season, unlike the species which can shed the lower leaves when stressed in the heat of summer. Growers of 'Prairie Princess' will also be delighted with its improved mildew resistance, helping to keep the foliage clean through the end of the season.