It seems to be related to Boston fern because it is. Sword fern, Nephrolepis cordifolia, is a less refined species of the same genus. It does not want to live as a docile houseplant. Instead, it prefers room to grow and spread in the garden. It has potential to spread a bit vigorously though. Containment protects adjacent smaller perennials or bedding plants.

Sword fern foliage is the same light and slightly yellowish green as that of Boston fern. It generally stands more upright though. Rather than hang softly from planters, like Boston fern does, it leans outwardly. Its pinnately compound fronds can grow almost two and a half feet tall. Pinnae might be about an inch and a half long, with a slightly grainy texture.

Sword fern is not particularly discriminating about exposure, moisture or soil. It can cling to trunks of Canary Island date palms and infest their canopies epiphytically. Sword fern is greenest with regular irrigation and shelter from harsh exposure though. Its evergreen foliage can discolor and partially defoliate when distressed. Grooming might be tedious. Healthy colonies may hide their old foliage.