Bold specimen plants, very popular with landscape designers. This species forms a clump of deeply cut and rather spiny dark-green leaves, bearing upright spikes of hooded, mauve and white flowers in summer. It is the most thistle-looking of any of the various forms available. Excellent for cutting, fresh or dried. Plants dislike wet soil during the winter months. May be divided or moved in spring, and any root pieces left in the ground will grow into new little plants.