Nephrolepis biserrata aka Giant Sword Fern

Nephrolepis biserrata is an evergreen fern called giant sword fern. It is a perennial with soft, non-woody growth. Its native range spans tropical America, Africa, and Southeast Asia. Kew places it across the tropics and subtropics. It grows in wet tropical climates, rather than cold ones. Some nurseries sell the species under the name macho fern. That name also appears on a named cultivar.

This large fern grows 3–8 feet (0.91–2.44 metres) tall. Its spread reaches 4–6 feet (1.22–1.83 metres). Long, pointed fronds arch out from the plant. The green leaves have a thin, papery feel. Their leaflets have edges with two sets of teeth. Hairs are also present on the foliage. Fronds can reach 8 feet (2.44 metres) in length. The plant keeps its leaves through the year. It has no flowers or fruit, and reproduces through spores. Sori on the leaf undersides form circles or horseshoe shapes.

In warm, moist sites, this fern grows and spreads fast. Stolons allow it to build large colonies over time. It can grow on larger plants as an epiphyte. It can also grow among rocks in tropical gardens. NC State lists outdoor hardiness in USDA zones 10–11. Outside tropical climates, gardeners grow it as a houseplant. Large rooms give its broad fronds space to spread. Containers and hanging baskets are also suitable uses. Outdoors, it serves as ground cover or a woodland border. Its size also suits the rear of a garden.

Keep the soil moist, but allow excess water to drain. The fern does not cope well with drought. It prefers slightly acid to neutral soil with organic matter. It can grow in poor soil when some organic matter remains. NC State lists loam, sand, and shallow rocky soils. Its light guidance includes deep shade and partial shade. The same account also reports growth in partial or full sun. Yellow leaves may point to too much water. Leaf loss can follow either too much or too little water.

This fern resists deer, but its spread can become weedy. NC State reports few major pest or disease problems. Florida fern caterpillars and fern scale can affect it. Check outdoor plants for pests before bringing them back indoors. These include mealybugs, aphids, scale, and fern mites. Gardeners can make new plants by dividing existing clumps. Some African cultures cook and eat the young leaves. This use does not establish that raw leaves are edible. ASPCA lists the species as non-toxic to cats, dogs, and horses.