A shrubby, herbaceous perennial that thrives in full sun and is sheltered. Produce tall flower spikes with dark purple-blue flowers and bright yellow-green calyces. Flowers begin to emerge in early summer, lasting right through to early autumn. Tolerates dry periods and light frosts. After flowering has finished, trimmed back by 1/3 of the plants height.
Grows to between 1.7m and 2m both in height and width,