The weed trimmer head is comprised of a sole plate having a diameter a circumference a plurality of pivot pins extending upwardly therefrom near the circumference. The sole plate also has a driving shaft extending upwardly therefrom from a center thereof. The driving shaft has a threaded segment thereon. A plurality of cutting blades are pivotally mounted to the plurality of pivot pins. A wingnut plate is also provided. This wingnut plate has a disc-like portion and wing blades extending on an upper side thereof. The wingnut plate has a threaded hole in its disc-like portion. The threaded hole is mounted to the threaded segment of the driving shaft and the wingnut plate is movable along the threaded segment, for selectively contacting or exposing the ends of the pivot pins.