ERYNGIUM. Widespread, particularly in South America. A large group, mostly of perennials, with a variety of ornamental features. The leaves are often presented in attractive basal rosettes and are variously shaped and colored. The flowers are tiny and carried in conelike clusters, often with circles of showy bracts beneath. Many are tough and easily grown, given a variety of exposures, soils and watering regimes. The following should be hardy to 10oF or less.
amethystinum. A striking plant, with narrowly divided, spiny basal leaves and intricately branched stems. The floral bracts are narrow, partially cleft and spiny, the flower heads nearly round. Both bracts and flowers are tinted with amethyst. One of the most beautiful of the group for floral arrangements. It requires well drained soil and is moderately drought tolerant.