Looking for a real jewel to add to your collection? Consider Eryngium 'Sapphire Blue', one of the hybrid forms of sea holly. From mid- to late summer, this hardy perennial bears cone-shaped flower heads ringed by steely blue bracts. The thistlelike stems and leaves have a blue tinge too.

Sea holly prefers well-drained soil and positively loves the sun: The more it gets, the more intense its flower color. The blooms look great in dried arrangements. 'Sapphire Blue' reaches 28 inches tall and 18 inches wide. Try it in a border with companions like black-eyed Susan or Shasta daisy. Look for Eryngium 'Sapphire Blue' at nurseries with good selections of perennials. Or order from