Boston fern or sword fern is a popular fern species that grows in tropical areas. It’s considered an easy-to-care-for houseplant and represents an elegant addition to any outdoor or indoor garden.
This plant grows delicate green-blue foliage and tiny leaves, reaching a maximum height of three feet in perfect growing conditions.
Yet, in some cases, the plant might start to show stress symptoms before it eventually dies.
So, why is my Boston fern dying? Is there anything I can do to help revive this plant?
If you’re asking these questions, you’ve come to the right place. Keep reading to learn more about caring for your Boston fern.
When the conditions in your outdoor garden or home are in favor of your Boston fern, this plant becomes one of the best choices for a beginner gardener.
It’s quite easy to care for and doesn’t have a lot of care requirements, as long as you’re maintaining it’s required growing conditions.
However, some symptoms show that your plant is suffering. If you notice some or all of these symptoms, then your Boston fern is dying.
- Your Boston fern isn’t growing in spring and summer.
- The plant is losing vitality and looks unhealthy.
- The fronds are drooping, and their ends aren’t crisp.
- The leaves are turning yellow or falling off.
- The leaves are turning brown because they’ve been ignored for too long.
- You notice a rotten smell coming from the pot.
- You see a lot of spots or discoloration on the leaves.
The good news is that unless you neglect the plant for too long, you can still save your Boston fern if you notice some of these symptoms.
Despite being a low-maintenance plant, your Boston fern will keep dying if you don’t provide it with the right growing conditions.
This plant is a slow grower and thrives in partially sunny conditions, where access to some shade can keep the plant healthy.
It prefers to grow in warm and humid conditions, so it reacts negatively to extremely hot weather when it’s grown outside in the garden or cold drafts from an AC when it’s grown inside.
Moreover, Boston ferns need to grow in stable conditions, so any fluctuation in the temperature or humidity level will harm the plant.
Because Boston ferns love humidity and moisture, you need to water them regularly. Misting the plant is recommended as it helps with protecting the leaves from getting too dry.
Misting is also essential if you’re growing your Boston fern in a dry climate. However, too much misting can actually make the plant prone to infections.
Boston ferns are hardy, so they rarely get infected with diseases and pests unless you’re neglecting your plant.
In most cases, choosing the wrong location to grow your Boston fern and not paying attention to it means that your plant will die.
It needs to grow in rich loamy soil, or the plant won’t be able to absorb the essential nutrients. When the soil has poor drainage, the Boston fern won’t survive.
Other than that, this plant will always stay in excellent shape, and you can keep it looking attractive by regularly pruning the dead fronds.
Boston ferns can encounter several problems that affect the plant’s growth. Luckily, by identifying the problem and adjusting the growing conditions, you’ll be able to save your plant.
Just like all types of ferns, Boston ferns thrive in well-hydrated soil. So, frequently watering your plant to keep the soil moist is essential.
Unfortunately, a lot of people make the mistake of watering their Boston fern too frequently. As a result, the soil becomes soggy, and the roots become unable to breathe.
Root rot will follow if you don’t do anything about the overwatering problem. This is a serious disease that suffocates the root system, and in most cases, saving the plant can be very difficult.
Overwatering can happen even if you don’t water your Boston fern more than you should.
For example, the roots will be kept in soggy conditions for too long if you choose a potting mix or soil with poor drainage. This also happens when you grow your Boston fern in a pot that is too big because the soil takes too long to dry out.
In addition, keeping the plant in low light conditions can also cause root rot because the soil doesn’t dry out. You should also adjust your watering schedule in winter and provide the plant with less water.
If the pot has no or few drainage holes, the excess water will suffocate the roots and lead to root rot. Moreover, when the drip tray is full of water, and you don’t empty it frequently, the roots will sit in the water for too long.
- The soil is wet, and the leaves are drooping.
- The lower fronds are turning yellow, followed by the upper ones.
- The leaves become too soft, and their tips aren’t erect.
- The tips of the fronds are turning brown.
- The soil takes too long to dry after watering.
- Old and new leaves are falling off.
- You can detect an offensive smell coming from the roots.
There are a few things you can do if you think that you’re overwatering your Boston fern and you notice some of these symptoms.
- Scoop your Boston fern out of the pot and inspect the roots. If you notice that the roots are mushy, brown, or black, and they emit an offensive smell, then they’re suffering from root rot.
- Use sterile pruning shears to trim all the rotten roots.
- Rinse the healthy roots to remove the old soil because the old soil contains the pathogens that cause root rot.
- Trim the wilting fronds and prune the foliage, so the trimmed root system can support the plant.
- Pick a new pot that is not too big or too small to allow the plant to grow. Make sure that it has enough drainage holes.
- Use loamy and fertile soil or a well-draining potting mix. Add perlite or some coarse sand to improve drainage in the soil.
- Water your Boston fern only when the top one to two inches of the soil feels dry. Make sure that you water your plant less frequently in winter.
In their natural habitat, Boston ferns thrive in tropical rainforests, where they get exposed to lots of humidity.
When the weather is too hot, your Boston fern plant will suffer. This also happens when you’re growing an indoor Boston fern near a source of warm drafts like heating vents or radiators.
So, if you’re growing your plant in too dry conditions, you’ll notice that the foliage is curling up.
When the humidity levels fall below 50%, your Boston fern will start drooping, and it won’t look as vibrant and attractive as it normally does.
This usually happens in winter, when your Boston fern suffers because of the heating systems that dry the air.
- The plant doesn’t look vibrant.
- The fronds droop, and the leaves don’t look erect.
- The foliage curls up.
- The leaves look yellow or brown.
There are a few things you do to improve the humidity conditions to help your Boston fern stay in shape.
- Measure the indoor humidity levels using a hygrometer if you’re growing your Boston fern inside.
- Use a humidifier, especially in winter, to increase the humidity levels in the house.
- Group your Boston fern with other plants because the transpiration can increase the humidity levels.
- Set up a humidity tray for your Boston fern by placing some pebbles on a shallow dish and filling it with water. Add the plant pot on top, making sure that the water doesn’t touch the roots, as this can lead to root rot.
- Mist your Boston fern occasionally, but avoid over-misting it because this can increase the risk of pests and diseases.
- Make sure that the plant is properly ventilated.
Boston fern thrives in bright indirect light that keeps the fronds vibrant and bouncy.
In its natural habitat, Boston ferns are usually planted where the canopy of big rainforest trees provides the needed shade. Overexposure to sunlight can scorch the plant and turn the leaves brown.
This is why it’s crucial to plant your Boston fern, where it can get some direct morning sunlight in addition to filtered, indirect sunlight throughout the day.
Too much sunlight can scorch the tender leaves, and the fronds will turn brown.
- The fronds look droopy.
- The leaves look washed out before turning yellow and then brown.
- The leaves become too dry and fall off.
Scorched Boston fern can be saved by following these steps.
- Use sterilized pruning shears to prune all the scorched fronds. This will maintain the plant’s energy to help it recover.
- Provide the plant with some shade by placing it near a window where it can get some indirect sunlight all day long.
- If you’re planting your Boston fern outside, transfer it to another part of your garden where it can grow in the shade of a big tree or another structure.
Without enough light, the fronds wilt, and the plant will look unhealthy.
Boston ferns are more tolerant of shade than excessive sunlight. A lack of bright sunlight won’t kill your plant, but it won’t flourish, and the fronds will look droopy.
Lack of sunlight increases the risk of overwatering because the soil takes too much to dry. It also makes the plant more prone to infections and diseases.
- Stunted growth of your Boston fern.
- The leaves look smaller than usual.
- The foliage looks dull and unhealthy.
- The fronds are drooping.
- Lower leaves turn yellow.
- The soil stays wet for a long time.
- In some cases, you would notice a foul smell coming from the pot.
Here are some steps to help your plant recover if it’s not receiving enough sunlight.
- If you’re planting your Boston fern outside, trim any overgrown branches if they’ve been blocking the sun.
- Transfer your Boston fern to another spot in your garden where it can receive more light.
- Place your Boston fern near a south-facing window, about 5 feet away. Placing it too near can scorch the leaves.
- If you’re growing your Boston fern in a room without windows, invest in some grow lights that help your plant thrive.
Underwatering is a less difficult problem to deal with than overwatering. However, it can still affect the growth of your Boston fern, and if you don’t do something about it, your plant will die.
Boston ferns thrive in moist conditions, so the soil shouldn’t be left to dry, even for short periods.
When the plant doesn’t receive enough water, the fronds start to droop, but it’s still able to survive for a while.
If you ignore watering the plant for too long, the leaves will turn brown and fall off. Eventually, the plant will die.
- Stunted growth.
- Older leaves fall off the plant.
- Droopy looks and the fronds look unhealthy.
- The soil is too dry.
- The leaves are turning yellow and then brown.
By following these steps, your underwatered Boston fern will be able to recover.
- Remove all the dead foliage, as this will help the plant recover faster.
- Set up a reminder on your phone to check on your plant.
- Place your Boston fern somewhere where you can easily notice it, so you don’t forget to water it.
- If you tend to leave the house for long periods, try a self-watering method that would keep your plant well-hydrated while you’re away from home.
Boston fern is a low feeder, but it won’t survive in poor soil conditions. This is why adding compost and mulch annually will enrich the soil enough to support the plant’s growth.
However, a lot of people make the mistake of overfertilizing their Boston fern.
With too many nutrients in the soil, the salts prevent the plant from absorbing the water and essential nutrients. As a result, the fronds become weak because they’re not well-fed, so they droop and become unhealthy.
The frond toxicity turns the tips of the leaves brown, and they fall off. If you don’t stop overfeeding your plant, you’ll end up with root toxicity, which eventually kills the roots.
- You notice yellow or white deposits on the soil because of excess salts.
- Stunted growth because the plant isn’t receiving enough nutrients.
- Brown and dry foliage.
- Droopy fronds that don’t look bouncy or healthy.
Here are the steps that can help you save an overfed Boston fern.
- If you’re planting your Boston fern in good and fertile soil, you don’t have to worry about adding extra food.
- Flush the soil using a garden hose. Run the water to wash off the extra salts.
- Avoid fertilizing the plant for at least six months.
- Repot the plant using a fresh potting mix.
- Apply a layer of compost and mulch once a year to maintain the condition of the soil.
- In spring and summer, use a diluted to 50% 20-10-20 liquid fertilizer to nourish your plant. Apply the fertilizer only every two or three months to avoid overfeeding your Boston fern.
- Avoid fertilizing the plant in fall and winter when it doesn’t experience growth.
Boston fern is usually infested by whiteflies, mealybugs, snails, and caterpillars, especially when it’s planted outside.
These pests infest the leaves and suck their juices, affecting the growth of the plant. When they’re ignored for too long, your Boston fern will die.
Inside the house, spider mites usually infest your Boston fern, but unfortunately, they can be overlooked because they’re too small to detect.
Treating pests depends on how early they’re detected because sometimes the plant is too damaged to be saved.
- Seeing bugs, especially on the undersides of the leaves.
- Finding a sticky mold that covers the undersides of the leaves, left by pests like whiteflies and mealybugs.
- Finding silky webs on the fronds or near the stem left by spider mites.
- Seeing multiple yellow or brown spots on the foliage.
- The fronds are drooping and wilting because of the bugs.
- Chewing bugs like snails leave a slimy trail and multiple holes on the leaves.
- A fungal infection can leave a brown web-like residue.
The early detection of bugs and pests will help you save your Boston fern before it’s too late.
- Inspect your plant regularly.
- Wash your Boston fern to drive whiteflies away.
- Hand-pick chewing bugs like snails, slugs, and caterpillars. You can also make sure that nearby surfaces are rough by adding crushed eggshells or gravel near the plant or on top of the soil to drive these bugs away.
- Use diluted isopropyl alcohol to drive mealybugs away, but do a test on one of the leaves first to make sure that you don’t burn the leaves.
- Use neem oil solution to treat your plant.
- Repot your Boston fern in new soil to treat fungal infections and apply a fungicide only when necessary.
In rare cases, tap water can actually harm your Boston fern.
Tap water contains calcium and magnesium, and these minerals build up in the soil, causing a white film on top of the soil. These minerals can prevent the roots from absorbing the water and the needed nutrients.
This water can also constrain nitrates from fertilizer run-offs, and these nitrates affect the concentration of different nutrients in the soil.
- Stunted growth.
- Wilting leaves.
- Fronds look droopy and their tips are brown.
If you think that your Boston fern is suffering because of tap water, you can try the following steps.
- Switch to filtered tap water or bottled spring water to water your Boston fern.
- Rinse the soil to remove the salt buildup.
If your Boston fern is currently struggling, it’s best to wait until you’ve treated the problem. An unhealthy plant will suffer from a transplant shock that might eventually kill it.
You can repot your Boston fern if you feel that it’s not growing fast enough because the pot is too small, so the roots are tangled. If you wait too long, the plant will become root bound and die.
Here are the steps to follow to repot your Boston fern.
- Plan to repot your Boston fern when it’s actively growing in spring and summer.
- Pick a suitable pot to repot your Boston fern, making sure that it’s slightly bigger. It should be bout 1 or 2 inches larger in diameter than the current one, as this will help the plant grow.
However, when the pot is too big, the soil will take much time to dry, and this can lead to root rot.
- Water your Boston fern, so the moist soil clings to the root.
- If you’re repotting the plant to deal with pest infestation or get rid of root rot, rinse the root ball properly and get rid of the old soil.
- Add about two or three inches of the fresh potting mix to the new pot.
- Hold the Boston fern in your hand, and guide your hand to place it carefully in the new pot. Avoid placing the plant too deep, as this might lead to root rot.
- Fill in the fresh potting mix around the Boston fern. Make sure that the soil is about 1 inch away from the top of the pot.
- Adjust the potting mix and pat the soil to remove any air pockets.
- Water your plant and place it in bright indirect sunlight for a few days.
- Examine the plant and water it when the top of the soil is slightly dry.
- Move the plant to its permanent location.
Boston fern is a popular houseplant that can be grown in an outdoor or indoor garden.
However, in the wrong growing conditions, your Boston fern can look droopy and unhealthy.
Luckily, adjusting the growing conditions can easily save your plant. You need to examine your Boston fern closely to identify why it’s dying, and in most cases, a minor change will be able to save your plant.
Growing up with a mom who filled her home (inside and out) with all sorts of plants, Lisa got her start in gardening at a young age. Living now on her own with a home and yard full of plants (including an indoor greenhouse), she shares all the gardening tips she’s gained over the years.