Yarrow (Achillea millefolium) is a hardy, easy-care perennial known for its flat-topped clusters of dainty flowers in shades of white, yellow, pink, or red that attract pollinators like bees and butterflies. It prefers full sun, tolerates heat, drought, and poor soils, and works beautifully in borders, meadows, or gravel gardens — deadhead or trim back after bloom to promote a neater habit and occasional rebloom.