Eryngium alpinum, also known as alpine sea holly or blue star, is a perennial plant that is native to Europe and is nothing short of fantastic! It is one of the showiest Sea Holly plants available on the market. The metallic stems and large thistle-like flowers mature to an intense steel blue summer through fall. When fully grown, the Eryngium alpinum can reach a height of 3 feet (0.9 meters), with a spread of about 2 feet (0.6 meters) wide.

An elegant species for the herbaceous border, Sea Holly has a long season of interest, perfect for exciting displays and for cutting, Eryngium adds interest to the winter garden. The summer-blooming blossoms, which are actually soft-to-the-touch, harden to long-lasting cut and dried flowers. Sea Holly can withstand severe frosts and is a tough plant for full sun in well drained, light soils. Sea Holly will also grow in partial shade, but prefers full sun. It is a deciduous, tap-rooted perennial that dislikes root disturbances.

General Instructions:  Amend your garden with compost or peat humus to enrich or loosen the soil, if needed, however Asclepias tuberosa is very adaptable to any loose, well-draining soil and will thrive in a good sandy loam. Mix a couple teaspoons of garden food or bone meal into the planting hole if desired, digging deep enough to plant the carrot like root vertically without coiling or breaking the roots. After planting you can water in once lightly and then they prefer a bit of a dry start when they are dormant in spring and have no foliage.