Check the plants one to two times a week for dead or wilting blossoms. Most daisy varieties flower continuously over several months, so the flowers peak and decline at different times.
Follow the stem of the wilted flower down to its base, where it emerges from the basal, or bottom, leaves.
Cut through the stem ¼ inch above the basal leaf cluster, using a clean pair of shears. Leaving behind longer stems doesn't improve the health of the daisy, and the dead stems are unattractive if left on the plant.
Deadhead the plants through the blooming period. Cut back the entire plant to the ground in fall after frost causes the whole plant to wilt.