Boston Fern Plants Care: Guide & Tips

Boston Fern Plants Care: Guide & Tips

Boston Fern Plants Care: Guide & Tips

The Boston Fern plant is an ancient, beautiful forest shrub that makes for a stunning indoor or outdoor addition. 

About Boston Fern Plants

Boston fern (Nephrolepis exaltata), also known as sword fern, is a very popular fern species that grows in many tropical and subtropical areas around the world. In North America, it is considered a common houseplant and is easy to care for, as it doesn’t require a lot of sunlight.

Outdoors, this plant thrives in swampy, tropical, and forested areas, and makes a great choice for shaded gardens in warm climates. Like most other fern species, Boston fern is a slow grower and is best planted outdoors in the fall or spring or indoors year-round.

Its sword-shaped, blue-greenish foliage contains tiny leaflets and grows from a spike, unfolding only when fronds grow large enough. Ferns are a national symbol in New Zealand, and in the maori culture the young, spiral-shaped sprouts of ferns are called “koru” which means new life, growth, and rebirth.


Common Names

Boston fern, sword fern, ladder fern, boss fern

Botanical Name

Nephrolepis exaltata



Plant Type

Herbaceous, perennial

Mature Size

2 to 3 feet tall and wide

Sun Exposure

Partial sun

Soil Type

Moist, well-drained

Soil pH

Acidic (6.0 to 6.5)

Bloom Time


Flower Color


Hardiness Zone

10 to 12 (USDA)

Native Area

Americas, Africa, Polynesia


Non toxic



Boston Fern Koru Sprout

Getting to Know Boston Fern Plants

Boston ferns like warm and humid conditions, and don’t enjoy extreme outdoor temperatures or indoor drafts from air conditioners or heating units. It’s crucial to maintain stable growing conditions for Boston ferns, as any fluctuations in the environment may quickly damage the plant and even kill it.

Water Boston fern frequently to prevent the soil from drying, and fertilize the plant regularly during its active growth stage. Misting your fern helps to raise the ambient humidity and is a must-do practice if you live in a dry climate, mornings and evenings work best.

Pruning your fern isn't a big chore either. Simply remove any dead frond to keep the plant looking attractive. Generally speaking, this plant only falls victim to pests or diseases when it's grown outside and neglected.

How to Care for Boston Fern Plants

Basic Care for Boston Fern Plants


Boston fern does best when grown in bright, indirect light. Too much shade can result in sparse fronds, and too much sun can burn the fronds quickly. For this, Boston fern is a good choice as a porch plant that receives filtered sun in the morning and afternoon shade.


Ferns like organic, rich, loamy soil with good drainage. Adding compost and peat to your outdoor garden or pot before planting is highly recommended. For a potted Boston fern, use a peat-based potting mix with mixed in perlite for increased drainage capacity. Poorly drained soil can cause root rot, which is one of the main killers of this plant.


The key to growing a Boston fern is to keep the soil lightly moist but not soggy the spring and summer when it is actively growing. This usually means weekly waterings for indoor plants, and even daily waterings for those grown outside in warm environments.

Regularly test the soil with your hand before watering. If the soil dries out, the fern’s foliage may quickly drop. During the fall and winter months, reduce waterings to every other week, but make sure the fronds don't dry out during this period of dormancy either.


Boston fern is a low feeder, however, that doesn't mean it will thrive in poor soil conditions. When it comes to outdoor ferns, make sure you mix the soil with 1 inch of compost and mulch annually to maintain good growing conditions. Indoor ferns should be fed once a month during the spring and summer using a standard liquid fertilizer at half strength.

Boston Fern Plant Pot

Boston Fern Pest and Diseases

A Boston fern grown outside can become a target for whiteflies, mealybugs, and chewing insects, like snails, slugs, and caterpillars.

Whiteflies can be found on the undersides of leaves where they suck the plant's juices and leave behind a sticky mold. Similar symptoms present for a mealybug infestation. Chewing insects will leave behind a slimy trail and cause holes in the leaves.

Whiteflies are best controlled by reducing the population with several blasts from the garden hose. This may take a couple of treatments.

Slugs, snails, and caterpillars can be controlled by handpicking or by providing a rough surface around the plant to deter them. This can be accomplished by sprinkling gravel, crushed eggshells, or coffee grounds at the base of the plant.

Indoor and outdoor ferns can also suffer from blight, a fungal infection that will leave the plant covered in a brow web-like mycelium. This condition can be treated naturally by simply repotting the plant in a sterile container and discarding the diseased soil in the process.

Boston Fern Plants Outdoors Forest

How to Propagate Boston Fern Plants

Boston fern is very easy to propagate by division. In fact, this is a great method to use for a fern that has outgrown its pot or is taking over a garden space.

  1. Gather a sharp pair of garden shears, a garden trowel, a spade shovel, a pot, and potting soil.

  2. In the spring, carefully separate a section of your fern with healthy roots attached.

  3. Fill a pot halfway full with potting soil or dig a new hole in the garden.

  4. Plant your cutting into either the mix or the ground, taking care to fully cover the roots when you backfill the hole with soil.

  5. Water the new division, and keep the soil lightly moist at all times.

  6. After a few weeks, gently pull on the base of the fronds. If you feel resistance, you know your fern has rooted!

Common Problems With Boston Fern

Overwatering your Boston fern can result in root rot, which causes your fern's fronds to turn grey and its roots to brown. Repotting and discarding the diseased soil is the best treatment for this problem. Root rot can also be prevented by providing ample drainage and airflow to the fern's roots.

Boston Fern Varieties

Boston fern comes in several varieties that change in appearance but whether you opt for a dwarf variety or a yellow one, the care still remains pretty much consistent.

  • Nephrolepis exaltata 'Compacta' is a short, compact, and upright version of the main Boston fern species. This type is sturdier than other varieties and a bit more drought tolerant.

  • Nephrolepis exaltata 'Florida Ruffle' is a medium-sized fern with feathery, ruffled fronds which grow in a dense clump. This plant thrives in an ultra-humid environment.

  • Nephrolepis exaltata 'Golden Boston' has gorgeous golden leaves and is considered low-maintenance, making a wonderful air purifier for the home.

  • Nephrolepis exaltata 'Rita's Gold' also grows yellow, almost chartreuse, fronds. It shimmers in the sunlight and compliments impatiens and begonias in a container setting.

  • Nephrolepis exaltata 'Fluffy Duffy' is a small, dense, and finely textured fern. This variety's feathery fronds look great in hanging baskets.

Bird's Nest Fern

Boston Fern Summary

Boston Fern are arguably one of the best houseplants to grow, especially if you live in humid climates. This ancestral looking plant, has huge deep green leaves that stem out of the center and reminds us of ancient forests and dinosaurs.

When it comes to automated plant care systems, Boston Fern are one of the plants that usually struggles with them, as it requires frequent but light watering. Only truly smart plant care systems like KORU can adapt to each plant's different needs, helping them to thrive by measuring light, temperature, humidity and soil moisture.

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