Eryngium plan. 'White Glitter' - Sea Holly

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. 

‘White Glitter’ typically rises in a globular mound to 2-2 1/2' tall. Spiny, egg-shaped, "glittering" white flower heads bloom abundantly throughout summer atop silver-green stems.