Ferns are valued for the lush, textured foliage they bring to shady landscapes. Gardeners often wonder if these perennials should be cut back in the fall to prepare them for winter. The answer is not a simple yes or no, but relies entirely on the specific type of fern you are growing. Pruning at the wrong time can harm certain varieties, so understanding your fern’s habit is the first step toward correct seasonal care.
Understanding Fern Types
Ferns fall into two major categories that dictate their care schedule: deciduous and evergreen. Deciduous ferns completely die back to the ground after a hard frost, entering winter dormancy. Common examples include the Ostrich Fern (Matteuccia struthiopteris) and the Japanese Painted Fern (Athyrium niponicum).
Evergreen ferns retain their green fronds throughout the winter months, offering color and texture when other plants have faded. Well-known species include the Christmas Fern (Polystichum acrostichoides) and the Autumn Fern (Dryopteris erythrosora). Knowing the category of your fern is necessary before deciding whether to prune.
When to Cut Back Deciduous Ferns
Deciduous ferns benefit from being cut back, but timing is important. Pruning should occur in late fall or early winter, after the fronds have turned brown or yellow and completely collapsed. This ensures the plant has extracted all available nutrients back into its root system before entering dormancy.
Cutting back these dead fronds is not strictly a matter of tidiness; it is a preventative health measure. Dead foliage lying on the crown or surrounding soil can trap excessive moisture, creating an environment where fungal diseases can easily take hold and survive the winter. Removing this debris reduces the risk of pathogens and pests overwintering near the plant’s vulnerable crown.
Use clean, sharp pruning shears to remove all dead fronds. Cut the fronds down to about one to two inches above the fern’s crown, the central growth point at the soil line. This clears the way for new, tightly coiled fronds, known as fiddleheads, to emerge unimpeded in the spring. Removing the spent material ensures the new growth receives maximum light and air circulation.
Caring for Evergreen Ferns Through Winter
Evergreen ferns should generally not be cut back in the fall, as their persistent fronds serve an important function. The green foliage continues to provide minor photosynthesis during milder winter periods, helping the plant maintain energy reserves. Cutting back all the fronds at this time removes the plant’s natural insulation and exposes the crown to freezing temperatures and harsh winter weather.
Care for these ferns involves highly selective pruning, typically performed in late winter or very early spring. Only remove fronds that are severely damaged, tattered, or browned from the winter cold. This selective removal should be done right at the base of the damaged frond, taking care not to disturb any new fiddleheads starting to form.
Winterizing evergreen ferns requires attention to the root zone. After the ground has frozen solid, apply a protective layer of mulch, such as shredded leaves or straw, around the base. This stabilizes the soil temperature and helps prevent the repeated freezing and thawing cycles that can heave the plant out of the ground. If the winter is unusually dry, providing an occasional deep watering prevents desiccation of the foliage and roots.