A very reliable and favourite garden plant, this perennial wallflower is evergreen and vigorous and produces neat tidy plants that are covered in flowers over a long period. Purple-Mauve blooms appear in long spires that are carried from late winter to summer, often lasting until the first frosts of winter. These are carried above attractive silvery-grey-green mounds of foliage. It will thrive in a sunny garden border, or even a large patio planter.