Grow and Care for Holly Fern

Grow holly fern in part shade, in soil that drains. Holly fern is Polystichum — Christmas fern is the native eastern kind. A tag that only says holly fern is often Japanese holly fern, which is Cyrtomium.

Give it part shade and soil that drains

Holly fern is a woodland plant. Dappled shade or the north side of a building keeps the fronds green; hot afternoon sun browns them. [1] Christmas fern wants that same shade, in soil that is dry to medium once the clump is established, as long as it still drains. [2] Japanese lace fern and Korean rock fern take a short dry spell after the first season, but they still want even moisture through summer. Western sword fern wants more humidity than Christmas fern. [3] Soggy soil around the crown is the primary cause of crown rot, especially in winter. Soft shield fern wants that same moist shade. Deer and rabbits seldom browse Christmas fern, tassel fern, soft shield, or Korean rock fern. Do not treat western sword fern as deer-proof.

Water a new plant, then only in a long drought

Keep the bed evenly moist — not soggy — until new fronds show. After that, Christmas fern takes a brief dry spell. Tassel fern and Korean rock fern still want even moisture, or the tips brown. Western sword fern wants more humidity than a dry-shade Christmas clump. A new plant that dries out crisps from the tips.

1. Water in after planting, and keep the root zone moist until new growth shows.
2. Then water Christmas fern in a long drought. Keep tassel fern and Korean rock fern more evenly moist through summer. Give western sword fern extra humidity if the air is dry.
3. Add a thin mulch of leaf mold or compost, kept off the crown.
4. Do not pile on fertilizer. Woodland soil is the aim.

Grow it in a draining pot on a shady patio

Christmas fern, Korean rock fern, soft shield, and western sword fern can live in a pot if the mix stays moist and the pot drains. A woodland clump is happier in the ground. For setting a nursery plant into a bed, see Planting Holly Fern.

1. Choose a pot with a drain hole.
2. Fill it with a humus-rich mix that stays moist but is not soggy.
3. Set the crown at the surface of the mix, in shade.
4. Water when the top of the mix starts to dry. Move a thin pot of western sword fern indoors if a hard frost will hit it.

Cut old fronds in late winter, before new fiddleheads

Holly fern stays green through winter, then the old fronds flatten. Leave them on the clump through the cold if you want them to shelter the crown, then cut them in late winter or very early spring, before the new fiddleheads unfurl. Do not cut new croziers. Do not cut western sword fern in fall — those fronds protect the next flush. [4]

1. Wait until late winter. Leave flattened fronds on the clump through the cold if you want the cover.
2. Cut old, flattened, or brown fronds at the base, close to the crown.
3. Stop as soon as new fiddleheads show. A cut into a crozier is a lost frond for the year.
4. Pull only loose brown material. Do not slice the crown.

Not a holly shrub, and not the Japanese holly fern

A holly shrub is Ilex — woody, with berries. See How to Grow Holly. Japanese holly fern is Cyrtomium — coarse, holly-shaped pinnae, often sold as a houseplant, not this genus. A Boston fern is Nephrolepis, a hanging houseplant. See How to Grow Boston Fern. Shop tags that say sword fern often mean that plant, not western sword fern. A wood fern or autumn fern is Dryopteris. See How to Grow Wood Fern. A lady fern is Athyrium. See How to Grow Lady Fern. A maidenhair is Adiantum. See How to Grow Maidenhair Fern. For which Polystichum you bought, see Types of Holly Fern.

If the fronds crisped, the bed dried out — water, do not move it into full sun.