Just when we're on the cusp of spring and summer in the Pacific NW, visitors to the nursery will often say, "I saw this really cool purple/blue/white spidery looking flower in a neighbor's flower bed, and I want one!" Chances are, it's a perennial cornflower or Bachelor's Button, and yes, they come in all three colors. 'Amethyst Dream' centaurea is a deep purple, fringe-like flower that contrasts beautifully against the gray-green foliage. Extremely hardy, perennial cornflowers will return each spring, growing to about 18 inches tall and almost two feet wide.