Shape the blue fescue grasses in the beginning of the growing season when you begin to see a hint of green developing in the clump. Remove only the outer perimeter of the plant with the pruning shears to make it attractively round.
Place the grasses you remove into the basket or bin to discard them.
Shear the blue fescue grasses after they finish flowering in the spring. Use the pruning shears or the hedge trimmer to remove the stalks holding the spent blossoms. Because the blossoms will drop seeds, shearing will not only maintain attractive plant shape, but it can also minimize spreading.
Discard the removed blossoms carefully into the basket or bin and discard them in the trash. The blossoms may reseed themselves in your compost if you place them into a compost pile.