Lygodium palmatum aka American Climbing Fern

Lygodium palmatum is a perennial fern that climbs by twining. Its common names include American climbing fern and Hartford fern. It comes from the eastern United States. In North Carolina, it grows chiefly in the Appalachian Mountains. It is rare there and threatened in several other states. Wild plants grow in thickets, bogs, marshes, and woods. These habitats range from open sites to shaded woodland.

In gardens, it reaches about 6–9 feet [1.8–2.7 metres] tall. Its spread reaches 6–8 feet [1.8–2.4 metres]. Long fronds wind around nearby plants for support. Individual fronds can reach 8 feet [2.4 metres] or more. Its form can be creeping as well as climbing. Growth proceeds at a moderate rate. The foliage is evergreen or partly evergreen, with green stems. The stems have no scent.

The green leaflets have no hairs and feel slippery. Sterile leaflets have three to seven lobes. These palmate divisions give each leaflet a hand-like shape. They measure about 0.08–0.17 feet [0.025–0.05 metres] long. Their width is about 0.17–0.33 feet [0.05–0.10 metres]. Fertile foliage grows near the top of the plant. Its leaflets have much finer cuts than the sterile ones. Spores form on the backs of these fertile leaflets. This fern produces neither flowers nor fruit.

Give it acidic soil that stays moist throughout growth. Loam and clay both suit its needs. It also tolerates sites that become wet at times. It grows in partial shade or full sun. NC State lists it for USDA zones 4–9. Bog gardens, pond edges, and woodland sites offer suitable settings. It also fits native plant gardens and naturalized areas. Its lasting foliage gives it a place in winter gardens.

Use this fern as an accent or a climbing screen. Choose its place with care near smaller garden plants. Its long fronds can climb over their neighbors. NC State rates its maintenance needs as moderate. The same source reports no known pest or disease problems. Deer seldom cause damage. Hartford fern has a history linked to Christmas decorations. Heavy gathering in Hartford, Connecticut, led to legal protection. NC State identifies it as America's first legally protected plant.