Common Yarrow

Common yarrow is a rhizomatous, herbaceous perennial with finely divided, aromatic foliage and flat clusters of tiny flowers. Its usual flowers are white to pale pink; flowering is strongest in summer, though regional sources report a longer season. ## Flowers and garden use The small flower heads attract bees, butterflies, and other beneficial insects. Use yarrow in sunny borders, meadows, naturalized areas, or as a loose ground cover; the stems also suit fresh and dried arrangements. It spreads by rhizomes and seed, so choose its place with room for a patch or plan to remove unwanted growth. In North America, the species includes native and introduced forms that can be difficult to distinguish, so choose regional seed or plants when local provenance matters. See the [USDA NRCS plant guide](https://www.nrcs.usda.gov/plantmaterials/mtpmcpg13974.pdf). ## Size and siting Plant in full sun and free-draining soil. North Carolina Extension gives a broad mature range of 1–3 feet tall and 1–3 feet 10 inches wide; the [RHS species profile](https://www.rhs.org.uk/plants/311/achillea-millefolium/details) lists 0.5–1 metre tall and a narrower 0.1–0.5 metre spread, so size and patch expansion vary. Yarrow tolerates dry or poor soil and needs little irrigation once established; water young plants during dry spells while roots settle in. It suits USDA zones 3–9 in the [NC Extension profile](https://plants.ces.ncsu.edu/plants/achillea-millefolium/common-name/milfoil/). ## Maintenance Remove spent stems if you want to limit seed spread or encourage another flush of flowers. [RHS guidance](https://www.rhs.org.uk/plants/achillea/how-to-grow-achillea) recommends dividing established patches every three to five years to renew vigor. You can leave seedheads standing through winter for structure, then clear old stems in early spring.