Yarrow is a hairy, aromatic perennial with a simple or branching stem. Flowerheads are minute, in dense, flat-topped, terminal clusters. Ray florets are minute, white, rarely light pink; the disk florets are light yellow. Blooms May–November. The leaves are finely dissected, fernlike, to 10 inches long, narrow-oblong, alternate. The odor is distinctively sweet and rather soapy, akin to the smell of chrysanthemums.
Several cultivars have been developed for the gardener, with a variety of flower colors.
Height: to 2½ feet.
Habitat and Conservation
Occurs in fields, pastures, prairies, roadsides, waste places, and disturbed sites. It is native to North America, Europe, and Asia. With its strong odor and host of potent chemicals, it has had many spiritual and medicinal uses in human cultures across the world. Its wild forms can be weedy to the point of invasiveness, but many horticultural varieties have been developed that are easier to manage in gardens.
Yarrow has a long history as a medicinal plant in China, Europe, and North America. In China, it was used for fortune-telling in the I Ching. Europeans long ago used it in magical amulets; today they use it in sheep fodder. Yarrow was found at a Neanderthal burial site in northern Iraq.
Many insects visit the flowers for nectar and pollen, and others eat the leaves. Researchers have found that some cavity-nesting birds, including starlings, line their nests with yarrow, whose aromatic chemicals may inhibit parasites.