The new and distinct Yarrow plant named Achillea ‘；Peter Cottontail’；, dense mounded habit, of upright heavily branched stems of medium height； linear, serrate, slightly-glossy, deep-green leaves； heavy flowering of white, predominately sterile flowers in large heads averaging over 100 florets per head beginning in mid-June and continuing for nearly seven weeks. The new plant is useful as a specimen landscape plant, mass planting or cut flower in arrangements.
