(Achillea millefolium) An electrifying mix of colors that breathes life into the landscape. Yarrow is an ancient herb appreciated for centuries as a healing plant. Ancient Native Americans chewed the leaves for toothaches, and an ancient Chinese proverb claims that yarrow brightens the eyes and promotes intelligence. Yarrow is a keystone plant for the drought-tolerant garden and is frequently grown in butterfly gardens. The roots also help to prevent erosion.