Some common names for Sea Holly are Miss Wilmott’s Ghost, rattlesnake master, and button snakeroot. The genus of the Sea Holly is Eryngium, and it is mostly native to Europe and the Mediterranean coastline. There are several species of Eryngium that have been cultivated for the gardener. It looks like a ‘Plume Thistle’ since the flower is burr-shaped, but the flowers are blue rather than mauve.
All that is required for this low-maintenance plant is a full day of sun and good drainage; prefers sandy soil. Finding a showy flower to grow in the sunbaked parts of the landscape, street, or along the driveway, is a challenge. Sea Holly plants will reward you with their blue flowers and will definitely add color to your problem areas. Their spiny-toothed leaves and clusters of blossoms provide a unique interest.
Deadheading is recommended and encourages extra blooms. Cut the flowers in late fall, but leave the evergreen leaves on the stalks for the winter. Since Sea Holly plants have a long taproot they are excellent for erosion control. Also the taproot allows them to tolerate drought, winds, salt sprays and sandy soils! Ornamental grasses, daylilies, and yarrow are outstanding companions for Sea Holly.