Cut back old, faded-looking fronds around the base of the fern with sharp pruning shears. Do this in the late winter or early spring before new growth emerges, and cut them back to the ground.
Cut the removed fronds into small, 1-inch pieces. Spread the cut leaves around the base of the plant as mulch.
Trim off any fronds that show signs of disease or insect infestation. Cut them back to the base of the plant. This can be done at any time during the year. If the entire plant shows signs of damage, cut the whole thing back to the ground. It will reshoot.