Should I Trim My Ferns?
Polystichum munitum, or Western Sword Fern, is a classic example of an evergreen fern that’s appearance will be improved from a spring trim. Pruning is absolutely not necessary, but by cutting off the old growth you make room for the ‘knuckles’ and fresh new fronds to show through. Other ferns will also benefit from this treatment, including deciduous ferns. The clipped fronds can be chopped and dropped around the base of the fern so all that green goodness can go back into the soil, as well as add a mulch to help with moisture retention and weed control.
There are a few exceptions to every rule, however! For further information, the Hardy Fern Foundation is a great resource. See below for its paper on Fern Maintenance: https://hardyferns.org/wp-content/uploads/2021/01/Cutting-Back-Ferns-The-Art-of-Fern-Maintenance-LG.pdf
Hardy Fern Foundation: https://hardyferns.org/