Eryngium planum, commonly called sea holly, is a coarse, clump-forming perennial that features a summer bloom of steel-blue, thistle-like flower heads on branched stems rising from a rosette of dark green basal leaves. Excellent selection for sun-baked areas of the landscape. Beds and borders. Effective as a single specimen or in groupings.
Easily grown in dry, sandy, well-drained soils in full sun. Tolerates poor soils. Tall plants may sprawl, particularly if grown in overly fertile soils or in anything less than full sun.