You might have heard that ferns, Boston fern especially, are one of the easiest plants to care for.
But you are seeing your Boston fern dying even though you took good care of it, probably according to the instructions on the tag that came with the plant. What is going on?
Before we get into why your Boston fern is dying, it should be said that Boston ferns are the easiest fern to care for, and as far as plants in general go, they are also considered easy. However, that is only true if the conditions in your home are in their favor. If they are, then this really is a hassle-free plant. If they are not, the plant can be dramatic and doesn’t grow as well as you would want.
To put your mind at ease, we find all of the calathea varieties we have (and Calatheas are notoriously fussy) to be livelier, happier, healthier than our Boston ferns. If you don’t have optimal conditions for your fern, you will need to adjust the plant’s care accordingly.
Read: How to Care for Boston Ferns
Why is My Boston Fern Dying
First thing, first. If this is your first Boston fern and you are caring for it according to the instructions on the tag – that tag just might be the reason why you are failing.
The tag’s information usually says you should water them once a week – this is very generic as not all homes have the same conditions. Temperature and air humidity, and many other things play a huge part in how fast the water evaporates from the soil and how often you will need to water your plant.
Most Common Causes for a Boston Fern Dying
There are quite a few things that can cause your Boston fern to start dying, some more common than others. We’ll guide you through the causes and help you identify the right one, as well as show you how to fix it.
Please keep in mind that there could be more than one issue causing your Boston fern to die – if you find one cause, do not assume it is the only one. You could have an issue with overwatering and pests at the same time, both destroying your plant.
The good thing with Boston ferns is, even though yours might be dying, they are hardy plants and aren’t easy to kill.
Even if yours is really struggling, the chances of bringing your dying Boston fern back to full life are pretty high. So even if your fern has started drooping, losing leaves, drying up, and its foliage isn’t as full as it used to be – don’t despair. Just keep on reading.
1. Overwatering
Overwatering is the number one cause for houseplants to die, this not being limited to ferns only. There are only a handful of houseplants that need constantly wet soil. Most plants don’t like being waterlogged and will quickly start deteriorating.
If the plant sits in water (the soil being too saturated with water), this will quickly lead to root rot, and root rot is fast in killing the plants.
You have probably heard that ferns love moist soil, and yes, that is true, but wet soil isn’t for them. There is a difference between wet soil and moist/damp soil, and every plant owner must learn the difference at one time.
How do you know if your Boston Fern is dying due to overwatering?
There are a couple of signs to look for when figuring out if this is the cause. If you let the soil dry between watering, you can probably rule out overwatering.
Note: overwatering doesn’t mean you are using too much water when you water your Boston fern (it isn’t strictly about the quantity). It is either watering the plant too frequently or not letting the excess water run out from the drainage holes in the pot as you water. This all makes the soil too saturated with water.
With overwatering, there is a high chance root rot will develop, and if the issue is too far gone, you might not be able to save your plant. But it’s always worth a try.
Symptoms to keep an eye on:
- soil constantly wet to the touch, doesn’t wan’t to dry reasonably fast
- plant loosing vitality, fronds drooping (soil wet)
- the leaves turning yellow (soil wet)
- tips of fronds turning brown (soil wet, tips usually not crisp dry)
- if rot root developed, you might notice rotting smell
Read: How to Know if You are Overwatering Your Plants
How to avoid overwatering and root rot?
Make sure the pot you have your fern in has drainage holes. This is the most important part – if you have a pot with drainage holes inside a decorative pot without holes, that is perfectly fine. However, if your Boston fern is planted directly in a decorative pot without drainage holes, well, this calls for overwatering and root rot.
When watering your Boston fern, make sure that all the excess water runs out off drainage holes (into the sink or somewhere else, not into the decorative pot)- no matter if you water from the top or the bottom. There should be no water in the decorative pot or the saucer. Do not allow your plant’s roots to sit in water.
Reduce water in winter – your plant requires less frequent watering in winter, so it is easier to overwater it during that time.
Water as necessary. While the tag usually says you need to eater your plant once per week, this will vary a home from home. Some need to water their Boston ferns daily, while others will only water them once every two weeks or so. Keep checking the top layer of the soil, and it should still be only slightly damp but not dry (and certainly not wet) before it needs watering again.
How to save your Boston fern that is dying from overwatering?
As overwatering can cause rot root, it is best to inspect your plant for any signs before anything else and act accordingly.
Move the plant out of the pot. Gently remove the soil from the roots, as much as you can without damaging the roots, using your fingers. Discard that soil.
Gently wash the roots. Slowly work your way through the roots, rinsing off as much soil as possible. You can also opt for spraying the roots with a mixture of hydrogen peroxide and water (1 part 3% hydrogen peroxide 5 parts water). This will kill many of the bacteria that causes the root rot.
Roots with root rot will be darker (brown, gray, or even black), mushy to the touch, and likely have a foul smell. Take a pair of sterile scissors or a knife and prune away those roots to prevent the spread. Depending on the quantity, you will also need to prune the leaves to give your plant the best chance to bounce back.
Done? If you are using the same pot, make sure you have cleaned and sterilized it before use. If it doesn’t have drainage holes, you can drill them or switch the pot for one with drainage holes.
Repot your fern, using new well draining soil. General potting soil for houseplants is OK. If you are mixing your own soil, you can add perlite.
From this point on, avoid overwatering. You can also add hydrogen peroxide solution occasionally to the water you use for watering to prevent root rot.
2. Underwatering
This issue is the easiest to identify as the soil is dirt dry, has probably shrunk, and became compact or the top layer crusted. And you can’t remember when was the last time you watered the plant.
Under-watering won’t cause your Boston fern to die as fast as overwatering. The plant will look really poorly if it’s regularly underwatered.
The tiny leaves will start drying up, first on the fronds’ tips and then the whole fronds. Once dried out, there is no turning back for those leaves. If you completely forgot about your plant, you will see many of these leaves fall off and make quite a mess.
As long as there is at least some, even one, healthy frond (or partially healthy), there is a chance to bring your dying Boston fern back to full life.
How do you know if your Boston Fern is dying due to underwatering?
Symptoms to keep an eye on:
- soil dry for long periods
- you do not remember when was the last time you watered your Boston fern
- leaves and while fronds drying
- lots of fallen off leaves near your plant
How to save your Boston fern that is dying from underwatering?
As long as there are at least a few healthy green leaves on your fern (even one), there is a chance to bring them back.
Prune all dead foliage. Once the fronds have died off, they won’t miraculously spring back to life. You can trim fronds that are only partially dried.
Water the plant. If the soil is dirt dry, you will need to soak it in water for an hour or so, so it loosens up. Make sure all the excess water drains out the drainage holes.
To prevent your Boston fern from dying from this cause in the future, make a habit of watering the plant regularly. Designating two to three days per week to check the soil is a great way to start figuring out your watering routine. You can use pen and paper to keep track or use a phone app. There are many on the market.
Alternatively, you can also look into buying a self-watering pot – you add more water to those, and the plant only takes as much as it needs. This way you won’t need to water as often.
3. Pests
Pests are a potential issue for all plants. If left untreated, any pest can kill your plant and spread to other plants in your home. No matter what issue you see with your plants, it’s always best to eliminate pests as a cause.
Carefully inspect your plant, looking for pests and signs of pests under the foliage. Some pests are easily spotted, while others, like spider mites, can be missed if you aren’t using a magnifying glass.
Is my Boston fern dying because of pests?
General symptoms to keep an eye on:
- visible signs of pests on the fern and the soil
- damaged leaves, spots, yellowing
- stunted growth
Spider Mite
Probably the most devastating pest as it is hard to notice until the infestation is already large. These tiny creatures are hard to see with the naked eye, you might see small brown, white, black or red flecks moving around, but they really are easy to miss. As their numbers grow, their signature webbing will show, and if you spot that, you can be certain you have a mite issue.
You can try and manually remove a large portion of mites by rinsing the plant with lukewarm water before treating the problem.
You will need to treat the plant for spider mites, either with commercial insecticide (follow manufacturers instructions) or by natural means.
Fungus Gnats
Fungus gnats won’t likely kill an adult plant unless the infestation is severe enough but can make the plant suffer. The larvae of fungus gnats destroy roots, and this is where the issue lies.
Gnats are easy to spot – they are small black flies, smaller and more slender than fruit flies. You will see them flying around plants and will most likely notice them when you water your plant. Even if you spot just a few, their numbers can actually be pretty high.
Yellow sticky traps work well for controlling the population, and there are many ways you can eliminate them.
Read: Tips for getting rid of fungus gnats on houseplants
Other pests can attack your plant as well.
4. Humidity issues
Boston ferns grow in humid areas, so they prefer higher humidity when they are in your home. They require humidity levels to be above 50% most of the time. While occasional drops won’t really hurt them, humidity constantly below 50% will cause drying up leaves and fronds and your plant looking poorly.
Chances are the low humidity won’t really kill your plant, so your Boston fern isn’t dying of it, but it will look pretty awful.
Humidity that is too high won’t directly harm your plant. However, if the humidity in your home is constantly high (70+), this will likely harm your home – think molds and fungus, and some of those can harm your plant too. If you increase humidity around your plants only, and not the whole room, 70+ is OK.
How to know if low humidity is causing your Boston fern struggling?
Measure the humidity in your home. You can get humidity meters under $10 – they come in all shapes and sizes with all kinds of different functions so choose one that fits you best.
If humidity shows as lower than 50%, you will need to raise the humidity around your plant or move the plant into a room that has higher humidity (bathrooms usually).
Measure the humidity directly next to your plant, as different areas of the same room can have different humidity – if you have your plant near a heat source, you can expect the humidity to be lower.
How to fix it?
Increase the humidity in your room, either the whole room or just next to your plant. You can also opt for moving the plant to a room with higher humidity.
There are many ways you can go about increasing the air humidity in the room or around your plants, so do what works best for you.
Read: How to raise humidity for your plants
5. Light
You don’t think watering or humidity is the issue, and you haven’t found any pests. Another possible cause for your Boston fern dying is insufficient light.
In nature, these types of ferns thrive in indirect light – the trees filter the sunrays, the light still being pretty bright, though when it reaches the fern.
If your fern is in a place where it doesn’t get enough bright indirect light, it will start to look poorly. It will benefit from the morning light. If you get strong afternoon sun, it’s best to filter that light for your fern.
While the plant will look poorly, it won’t die because of low light.
6. Overfertilization
You think you are doing everything right as far as watering goes and the air humidity. Your plant is also getting the right light, and it should thrive. No pests either… What’s the deal?
Another issue to consider is how often you fertilize and how much fertilizer you use? Check the box/bottle of your fertilizer and ask yourself if you followed the instructions or have you gone overboard? We would even suggest using the fertilizer in less than recommended amounts.
If you’ve over-fertilized the plant, probably in hopes for it to develop fuller nicer fronds faster, the effect will be just the opposite.
Too much fertilizer will lead to too much mineral, and salt builds up in the soil – and the plant will suffer. The growth will be stunted; leaves can start to dry up and become yellow. If you continue overfertilizing, or this has been going on for too long, your Boston fern can die.
How to Fix it?
Water your plant excessively, letting the water run through the soil a few times. This will wash out some of the minerals and salt that was building up in the soil. Do not fertilize again this season.
You can also opt for repotting the plant into fresh soil.
7. Tap Water (rarely)
Boston ferns are OK with tap water, even if you don’t let it sit overnight. However, when the water is really heavy in minerals or highly chlorinated, issues can arise.
If you suspect your water isn’t ideal, let it sit for a day before watering or use filtered water.
