This pretty perennial has a basal clump of dark green leaves; it is fully hardy and a strong grower. The flowers are a profusion of tufts of tiny purplish blue flowers borne on upright, wiry stems from June to September. It likes a sunny situation and well drained soil. Can be propagated by stem cuttings in late summer or autumn. Height to 2 m. An attractive bedding plant also popular for cut flowers. Hardy plant, low maintenance, easy to grow.