In drought-prone areas or spots that need a splash of color, the unusual perennial Sea Holly Roots Blue Star is an excellent choice. Its tall, straight, gray-blue stems provide sturdy support for thistle-like, metallic blue flower heads, keeping them upright and highly visible to passing butterflies and bees. Thriving in full sun, the two to three inch blooms emit a striking blue hue that is simply stunning when planted in groups or large masses.