Superb clump former with bright blue flowers and stems in summer, dark green silver veined leaves. Can be air-dried and useful for floral arrangements. Well,drained soil in full sun. Can be cut back to encourage a second flush of flowers.
Both the leaves and the roots of sea holly are edible. Linnaeus recommended boiling the young flowering shoots. The shoots are sometimes blanched that is, grown without light so they will be very pale in color – and served as an asparagus substitute. The roots, boiled or roasted, taste like chestnuts.
Sea holly has an extensive root system, so it is sometimes used for erosion control. Both the foliage and the flowers are dried for use in dried flower arrangements. Deer tend to dislike Eryngium. Sea holly has a long tap root, which makes transplanting difficult. Place seedlings in their permanent location for best results.