Ferns are tropical plants that don’t take too easily to chilly weather. So how can you take care of your Boston ferns and meet all of their needs during the cold season?
What you’ll first notice about a Boston fern in the winter is that it doesn’t go into dormancy. This plant thrives all year round, especially if it’s indoors. They might go into a semi-dormant state, where their growth slows down and their fronds turn brown.
That being said, Boston ferns need special care if you want to preserve their beautiful fronds in the winter, which can be challenging.
This begs the question of how to make a Boston fern go dormant. Stick around to find out!
Boston Ferns and Dormancy
The Boston fern, also known as the sword fern, is often seen hanging beautifully in a basket indoors or on a porch outdoors. You’ll find several types of Boston ferns like the Florida Ruffle, Rita’s Gold, or the Golden Boston.
An important thing to know about Boston ferns is that they don’t go into dormancy during winter. Unlike deciduous ferns, Boston ferns are an evergreen perennial plant that thrives in hardiness zones 9 to 11. In other words, a Boston fern doesn’t lose its fronds during the winter season and continues its growth, albeit slower.
Most plants go through a period of dormancy where they stop growing in the winter and need less light, and Boston ferns aren’t that different. Their growth slows down and they rest slightly before blooming with brighter greens in the spring. However, they don’t completely hibernate.
Caring for your Boston fern during winter the same way you do in summer may cause its fronds to become dry and brown. This usually fools most plant lovers into thinking the plant has gone dormant.
With that in mind, in order to preserve your Boston fern during winter, learning how it survives and how to take care of it the right way is essential.
What Happens to a Boston Fern in Winter?
If you bought a Boston Fern in summer, you would be amazed by how much it changes in winter! The plant’s altered state becomes more understandable once we explore its origins and native habitat.
Boston Ferns are native to the tropical rainforests of South America, specifically, northern Argentina and southern Brazil. These locations are warm and humid, with a thick canopy that only lets filtered sunlight reach the ground dwellers, like ferns.
That’s why, Boston Ferns seem uneasy during the winter. They go through a state that resembles hibernation in animals, where the fern’s metabolism slows down, in response to the drop in temperature.
Here are the main changes you should expect to see:
- Significant reduction in growth
- Lower watering needs
- Reduced light dependence
- Potential color changes
- Loss of vitality
How to Make a Boston Fern Go Dormant
Seeing as Boston ferns don’t go into complete dormancy, how can you make them go dormant? It’s actually pretty simple: overwintering!
Boston ferns might not survive a frost, but moving them just in time before the extreme cold can help you keep the ferns alive during wintertime.
In winter, you’ll have to take care of your Boston fern differently than in the summer. So, let’s see how this goes!
Step 1: Find the Right Location
Overwintering your lovely Boston ferns starts with finding the perfect location. If you leave your Boston fern outdoors during winter, you might as well forget about it. Yes, Boston ferns are tough plants, but they aren’t cold-hardy ones!
When growing a Boston Fern outdoors, you’ll notice they prefer a place with high humidity and partial shade. They thrive in daytime temperatures around less than 95 ºF, and around 60 ºF at night.
When it’s wintertime, Boston ferns have to be moved away from the frost, preferably indoors. Note, however, that they usually cause a mess when kept in a hot, dry home. So, if your home isn’t the best environment for them, consider placing them in your shed, garage, or basement.
When you move the Boston fern, it’s best to gradually acclimate it to its new location. Winter care for a Boston fern doesn’t necessitate providing a lot of light. Setting the plant in a dark place is fine for the fern because it’s in a resting stage.
Step 2: Start Pruning
It’s well-established that Boston ferns are one of the messiest plants to overwinter. Moving the plant before pruning can result in a huge mess.
Ideally, it’s best to prune your Boston fern to prepare it for repotting and the change of location. Boston ferns respond greatly to a good trimming. Pruning encourages more growth and corrects any dull or irregular fronds.
To start pruning, look for the old, yellow, or brown fronds. Sometimes you can even see leafless stems just dangling from the plant. Those are all good signs that you should start the trimming process. When pruning a Boston fern, use clean and sharp pruning shears or scissors.
Don’t trim the top of the plant. Instead, trim the discolored fronds on the side at the base of the fern. If you cut your fern down to just above where new growth begins to emerge from, it’ll aid its health and increase its longevity.
Step 3: Cut Back on Fertilizers and Water
As we’ve said before, when it comes to growing during the winter season, Boston ferns slow their growth significantly. Hence, fertilizing a Boston fern too much is often the reason why they die during the winter months.
Fertilize your Boston fern about once every 2-3 months when overwintering. This is about half the rate of fertilization in summer.
When it comes to watering, you’ll notice that they don’t need that much either. To check if they need to be watered, touch the soil and see if it’s dry or moist first.
With this knowledge, you’ll find yourself watering your Boston fern just once or twice per month. Watering the fern will also help flush out excess salt in the soil from the fertilizers and keep the plant looking great.
Troubleshooting Boston Ferns’ Common Winter Issues
You might do all the necessary winterization steps, and still, your Boston Fern exhibits signs of distress and malady.
Here are some common Boston Fern issues and the best treatments.
Dry Brown Fronds
Winterizing Boston Ferns implies reducing its watering frequency and quantity. However, the plant still needs some water to stay alive. A dry environment can also stress the plant and cause its fronds to turn brown.
It’s best to water the fern regularly but at longer intervals. Also, keep the plant in a humid location, away from dry air or vents.
Drooping Fronds
Cold temperatures often cause the fern’s fronds to become droopy and leathery. But there are a couple more culprits to watch out for; root rot and lack of humidity.
Placing the fern in a warm humid location is ideal. If you suspect that the soil is holding too much water and rotting the roots, then inspect the base of the plant. Root rot isn’t hard to spot, so if you see any of its signs, clean up the roots and repot the fern in clean soil.
Yellowing Leaves
Winterization means reducing light and fertilization, but not eliminating this sustenance entirely. Yellowing leaves are often a sign of nutrient deficiency or insufficient light. Another cause might be overwatering, but that’s not too probable if you’re winterizing the fern correctly.
Pest Infestations or Disease Outbreaks
Tropical plants naturally show signs of distress when the temperatures around them become exceedingly cold. This means that their resistance to pests and diseases wouldn’t be too high.
If you spot signs of pest infestations, wash the fern with warm water and a tiny bit of dish soap. You can spray it with neem oil to deter the bugs. Fungal and bacterial infections are also probable during these times, so ask for professional help if that happens.
Final Thoughts
If you live in a cold region and your Boston fern is starting to look droopy and lifeless, try moving it indoors during the fall and winter months.
While they don’t go into full dormancy, overwintering Boston ferns is a very simple process that’ll help keep them healthy. Just make sure to pick a proper location and cut back on fertilizer. You’ll also need to prune the plant to correct dull and irregular fronds.
After a full summer of growth, Boston ferns should be easy to keep alive during the cold months of the year using the tips shared in this post.
Good luck!
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.