A trimmer attachment for use with a lawn mower includes a deck mounting plate configured for attachment to the lawn mower, one or more mounting tabs extending up from the deck mounting plate, a curved pivoting arm rotatably coupled to the one or more mounting tabs, a pivoting motor for rotating the pivoting arm, and a trimmer head coupled to the pivoting arm. Rotation of the pivoting arm by the pivoting motor causes the trimmer head to rotate between a stowed position and an engaged position.