boston fern care: how to keep them happy

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boston fern care: how to keep them happy

plant description

The Boston Fern is known for its arching, lacy fronds that filter light and purify the air of common household pollutants. Commonly known as the Sword Fern, this forest-loving plant thrives in cool, humid conditions and enjoys a stable temperature environment. Sword ferns are easy to find in garden centers and are especially popular as hanging plants. They pair perfectly with diy hanging macrame planters! Boston Ferns have narrow, blade-shaped fronds that sprout in vibrant, bright green and mature to a deep sea-gree. Smaller fronds stand upright and will bow as the mature, forming a spray of arching stems that grow to a full height and width of 3 to 5 feet.

plant facts

common nameSword Fern, Ladder Fern, Boss Fern, Tuber Ladder Fern
botanical nameNephrolepis exaltata
no. of varieties20-30
biological life cycleperennial
mature size3-5 fet tall
time to maturity2-5 years
originTropical regions of ​​Florida, West Indies, Mexico, Central America, South America, Polynesia and Africa
light conditionsbright, indirect light
soil typemoist and well-draining, amended with organic matter
soil pHacidic to neutral
USDA Zone10-12

popular varieties

Popular varieties of the Boston fern include Nephrolepsis exaltata ‘Compacta’, Nephrolepsis exaltata ‘Dallas Jewel’, Nephrolepsis exaltata ‘Golden Boston’, Nephrolepsis exaltata ‘Verona’, and Nephrolepsis exaltata ‘Fluffy Ruffles’,

how to take care of a boston fern

light 🔆

Best light: bright, indirect light

Sword ferns love bright, indirect sunlight and partial shade. Fronds and soil will dry out quickly when placed in direct sunlight. You may need to adjust the placement of your Boston Fern indoors throughout the year as lighting conditions shift.

water 💧

Water requirements: maintain moist soil and water frequently

These plants are thirsty! Boston Ferns need consistent water to thrive, and it’s important to make sure this plant’s soil never dries out completely. Depending on light exposure, your Boston Fern will need water twice weekly to daily during the growing season. Reduce watering to once weekly during colder months.

Potted Boston Fern on a desk with light

humidity 🌫️

The Boston Fern plant loves a high humidity level of around 80%. There are a few ways to boost the humidity in a room to suit your fern’s liking. We recommend regularly misting the plant or placing it in a steamy bathroom with appropriate light, since typical household humidity is only 10-15%. Browning frond tips and yellowing are a sign that your fern is craving higher humidity.

temperature 🌡️

The Boston Fern prefers cool to mild room temperatures, ideally between 55°F(13°C) and 75°(24°C), though they’re happiest on the cooler end of this range.

boston fern care

fertilizer 💩

fertilizer preferences: Fertilize your Boston Fern with a diluted liquid houseplant fertilizer (½ strength is usually sufficient) once a month from the spring to early fall. Do not fertilize the fern between late fall and winter when the plant is dormant.

soil 🪨

soil type: moist and well-draining, amended with organic matter 

pH level: acidic to neutral

Boston Fern plants are most content in moisture-retentive, well-draining soil. Look for a loamy potting mix containing peat moss (sphagnum moss) for moisture retention and perlite to improve soil aeration. Sword Ferns are fine with soil that is acidic to neutral.


Although Boston Ferns take their time growing to full size, slow growth may also be a sign that your fern is root bound and needs repotting. This can also be the case if your fern needs more frequent watering, or water is running through your plant – a sign that roots have consumed the existing soi.. Re-pot Boston Ferns in spring, using a pot only one size larger than the existing pot to avoid drowning the root ball.

propagation 🌱

Ferns reproduce through spores (the tiny yellow-brown dots along the underside of leaf blades) rather than flowering, which means the easiest way to propagate them is through plant division. 

Start by preparing your workspace – I like to do this outdoors, but you can also cut a plastic garbage bag and work there. Remove your fern from its cover and inner pot, and place fern-side up on your work surface. Slice into the root ball like a cake, using a sterile, serrated knife, and divide into the desired number of sections. Re-pot your new ferns in new containers with fresh soil, and water thoroughly.

Boston Fern growing wild

pruning 🌿

Pruning keeps the Boston Fern healthy, full, and pest-resistant. Regularly remove dead fronds, or any tips that are drooping and brown. It’s best to prune from the sides as opposed to the top of sword ferns, since new growth typically sprouts from the center of the plant. Pruning can release spores that stain hands and furniture, so bring your sword fern outside for its haircut if you’re worried about mess.

pests and diseases 🐛

pests: spider mites, mealybug, scale, caterpillars and thrips

Grown indoors, Boston Ferns occasionally fall prey to spider mites, mealybug, scale, caterpillars and thrips. If you notice wilting, sticky residue on leaf fronds, or stunted growth, your fern may have a scale infestation. Examine the underside of fronds regularly for mealybug, paying attention to where fronds meet the main stem. Use an insecticide as soon as you identify pests, and keep your fern away from other houseplants until the infestation is under control. 

plant care tips

1. As an epiphyte, the wax plant absorbs some essential nutrients through its leaves. 1. As well as being a popular house plant option indoors, this evergreen fern is a popular outdoor plant. Plant this fern outside in USDA zones 10-12.

Common Problems / FAQs: 

1. Fronds turn yellow, brown

→ dry air, increase humidity 

2. Grey fronds, wilting, slowed growth

→ It’s possible the plant is experiencing root rot. Check the roots to see if they are mushy or grey in color. If the roots are rotting, it’s best to remove them with shear, add fresh soil to the pot, and replant the fern.

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