Guide to Ferns: 13 Ferns for Indoor and Outdoor Gardens

Ferns are among the oldest types of plants on earth, with fossil records indicating they existed over 360 million years ago in the Devonian Period. These perennial plants are flowerless and seedless, reproducing by spores released from the undersides of their leafy or feathery fronds. There are over 10,500 known species of ferns today.

Ferns are low-maintenance indoor plants, but it's important that you mimic their natural outdoor environment when you grow them in your home. Ferns grow best indoors when kept in the shade and misted with water daily to simulate humid outdoor conditions. Some of the most common types of ferns to grow indoors are:

1. 1. Bird's nest fern: Asplenium nidus is an epiphytic plant, meaning that it grows in trees or on other plants in its natural environment. To grow a bird's nest fern indoors, place it in a hanging basket or mount it to a board. This fern species prefers indirect sunlight, grows up to three feet high and two feet wide, and becomes drought-tolerant once it establishes new growth. The bird's nest fern grows crinkled fronds in indirect light and flat fronds in full shade.
2. 2. Button fern: Pellaea rotundifolia is an evergreen fern that's extremely easy to grow indoors, as it doesn't require moist and humid conditions. The button fern has arching fronds with dark green, leathery button-shaped leaflets (pinnae) attached to a thin stem. You can also grow button fern in outdoor gardens in USDA plant hardiness zones eight and nine.
3. 3. Cretan brake fern: Pteris cretica is a bushy evergreen fern that has long fronds with sword-like leaves. The leaves have dark green edges with a thick, pale green stripe down the center. The Cretan brake fern requires indirect bright light and humid conditions to thrive. This type of fern plant can also grow outdoors in warm, subtropical climates.
4. 4. Holly fern: Cyrtomium falcatum is an ornamental houseplant known for its bright green, glossy leaves. This hardy, shade-loving popular fern has leaves that grow longer than one-and-a-half feet and are composed of six to ten smaller pairs of leaflets. The holly fern can grow both indoors and outdoors, but it is one of the easiest types of indoor ferns to grow.
5. 5. Royal fern: Osmunda regalis is a deciduous fern that thrives in shady environments with damp, acidic soil. This flowering fern plant has lush, long fronds—imposing green leaves that provide the inspiration behind its royal name.
6. 6. Rabbit's foot fern: Davallia fejeensis is a low-maintenance fern variety that loves bright, indirect sunlight and high humidity (daily water mistings are key for producing robust growth). Native to Fiji, the rabbit's foot fern gets its name from its fuzzy rhizomes that extend above the topsoil. Rabbit's foot ferns are typically grown indoors, but they can also serve as a wonderful low-growing groundcover plant outdoors.
7. 7. Staghorn fern: Ferns of the Platycerium genus are epiphytic plants similar to bird's nest fern. To grow a staghorn fern indoors, mount it to a board or place it in a hanging basket to mimic its natural growing environment. Also known as elkhorn fern due to the antler-shaped leaves that grow from its rhizome, the staghorn fern requires thorough watering to grow. Ensure that it stays moist by occasionally dunking its entire mount board underwater.

Outdoor ferns bring a tropical ambiance to any home shade garden, making them a popular groundcover plant. Keep your outdoor fern plants out of direct sunlight to avoid burning their leaves, spread a layer of mulch on top of your soil to create the moist conditions that ferns require. Some of the most common types of outdoor ferns to grow are:

1. 1. Christmas fern: Polystichum acrostichoides is an evergreen ornamental fern with leathery, dark green fronds that are two to three feet long. Its fronds resemble the needled leaves of a pine tree, which is how it gets its name. Christmas fern grows in full shade or partial shade conditions and thrives in USDA plant hardiness zones three through nine.
2. 2. Boston fern: Also known as sword fern, Nephrolepis exaltata is an evergreen perennial herbaceous plant. The arching branches of this tropical fern make it ideal for placement in a hanging basket. Although often grown indoors as a houseplant, Boston ferns flourish outdoors in the right conditions. Boston ferns require a cool environment with partial shade or full shade, as their fern fronds are easily scorched in direct sun. Boston fern cultivars ideal for outdoor growing include Tiger Fern (Nephrolepis exaltata ‘Tiger Fern’) and Lemon Button Fern (Nephrolepis cordifolia 'Lemon Buttons').
3. 3. Lady fern: One of the more low-maintenance ferns due to its tolerance to sunlight, Athyrium filix-femina has lush bright green foliage with frond stalks in various shades of purple, red, and green. This perennial fern grows two to five feet tall, depending on the type, and while it prefers moist soil, it becomes increasingly drought-tolerant as it matures. Its rhizomes and emerging fronds are poisonous when raw, so avoid planting lady fern if you have an outdoor pet. Cultivars that are good for outdoor growing include the Japanese painted fern (Athyrium niponicum pictum), Lady in Red (Athyrium filix-femina 'Lady In Red'), Silver Falls Japanese painted fern (Athyrium niponicum 'Silver Falls'), and ostrich fern (Matteuccia struthiopteris).
4. 4. Maidenhair fern: Featuring dark stripes and bright green, delicate fronds, maidenhair ferns require a humid climate and moist soil rich in organic matter. They're extremely sensitive to direct sunlight and should only be planted in full shade locations. Types of maidenhair ferns suitable for outdoor growing include the American maidenhair (Adiantum pedatum), northern maidenhair (Adiantum pedatum aleuticum), and southern maidenhair (Adiantum capillus-veneris). Some varieties of maidenhair ferns like the delta maidenhair (Adiantum raddianum) are also suitable for growing indoors and flourish in small containers inside a high-humidity terrarium.
5. 5. Osmunda fern: One of the tallest varieties of ferns available to home gardeners, osmunda ferns thrive in moist, shady, swamp-like areas such as the Ozark region in Missouri. Types of Osmunda ferns recommended for outdoor growing include the cinnamon fern (Osmunda cinnamomea) and interrupted fern (Osmunda claytoniana).
6. 6. Wood fern: One of the most adaptable varieties of fern due to its tolerance of various light conditions (full shade to indirect light), this medium-sized hardy fern is also drought-tolerant once mature, which makes it a great choice for first-time fern growers. Types of wood ferns ideal for outdoor growing include the autumn fern (Dryopteris erythrosora), crested buckler-fern (Dryopteris cristata), leatherleaf fern (Rumohra adiantiformis), and marginal wood fern (Dryopteris marginalis).

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