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Boston Fern Hardiness: Everything You Need to Know

Boston Fern Hardiness: Everything You Need to Know
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Boston ferns are dazzling plants that add a fresh and calming effect to your place. While these plants are easy to take care of and aren’t overly needy, it’s essential to give them proper care.

They can be grown both outdoors and indoors. Whether you choose to put them outdoors or indoors, they need certain conditions to thrive.

Generally, it’s best to grow them outdoors in winter and fall.

To help you properly care for this beautiful plant, we’ll tell you all about the ideal conditions for Boston fern and all about their hardiness.

Boston Fern Hardiness

It’s important to grow Boston ferns in the right environment.

Their natural habitat is in rainforests filled with humid air and shade.

Boston ferns need certain temperatures to grow in because being exposed to the wrong ones can damage them.

Plus, they are intolerant to extreme temperatures outdoors or blasts of air from vents or outlets indoors.

Boston Fern Hardiness Zone

Boston fern’s hardiness zone is 9 to 11, which means that this plant can’t withstand extreme cold or heat as these conditions hinder its growth.

As a tropical houseplant, it’s primarily grown indoors. However, it can be grown in mild conditions outside with proper care.

Boston fern also thrives in humidity, as it loves water, unlike other plants. That makes it intolerant to drought conditions.

Boston Fern Cold Hardiness

Boston ferns are tropical plants and cannot endure freezing. These plants thrive in indirect sunlight or partial shade and prefer temperatures of 65°F–75°F.

However, Boston ferns can’t tolerate extreme temperatures; they should be covered in low temperatures below 40°F.

So, while they can take a one-time blast of cold air, it’s best to bring them indoors when the first frost hits.

Because these plants go into dormancy during winter, it’s best to store them in a dark or semi-dark spot in your garage that doesn’t drop as low as 45°F in temperature.

After winter, you’ll find your ferns reviving again like a phoenix.

Boston Fern Hot Hardiness

We’ve already established that these plants need the temperature to be just right, neither too hot nor too cold. Extremely hot weather can be harmful to them, causing them to wither.

So, Boston ferns prefer cooler temperatures and can’t tolerate hot conditions that rise above 95°F or higher.

How to Grow Boston Ferns

To enjoy the full welcoming sight of their accretive green leaflets, it’s important to provide them with their needs of the soil, water, and light.

Here are these needs:

Soil Needs

This plant thrives in damp, rich soil with good drainage. It’s best to grow a Boston fern in a mixed pot filled with peat moss and vermiculite.

Regular fertilizing is preferable, but don’t overdo it because over-fertilizing can cause browning and withering of the leaves’ tips.

If you notice the leaves yellowing, it might be a sign of low nutrients.

Light Needs

Boston ferns grow originally protected by high dense trees that provide them with needed shade to thrive. So, it’s important to plant them in similar conditions.

That’s why a covered porch outside or indoor spaces are the ideal places to grow these plants.

In case there’s no porch, surrounding Boston ferns with sun-loving plants is a good solution. Or, you could go for a screen door to keep your ferns sheltered.

Boston ferns should be exposed to moderate amounts of both shade and light. Too much shade can result in thin, lifeless leaves, while too much light might cause the fronds to scorch.

During fall and winter, Boston ferns should receive at least two hours of the indirect morning or late afternoon sunlight daily.

Yet, when the sun grows more intense in summer and spring, these conditions should adjust. A location of partial shade throughout the summer is preferable.

Water Needs

Water is a Boston fern’s best friend. These plants love water and humidity, and it’s best to make sure they grow in moist soil because dry soil can harm them.

On the other hand, the soil shouldn’t be wet and soggy because too much water can cause root rot. So, you should regularly test the soil to be sure of its moisture.

The yellowing of the leaves can be a sign of low humidity. Therefore, if your ferns are turning yellow, make sure you get a humidifier.

To increase moisture and humidity around your fern, you could place the plant’s pot on a tray filled with water and pebbles. Or you can give your plant a light misting every week.

Weekly waterings are best for indoor ferns, while more regular waterings are when they’re planted outside in hotter climates.

However, it’s better to limit watering to every other week throughout the fall and winter months. Additionally, you’ll want to ensure the leaves are getting enough moisture while they’re dormant.

Common Pests of a Boston Fern

Boston fern is prone to some common pests, such as scales, slugs, and mealybugs. So, it’s best to treat these pests quickly before they turn into an infestation and damage your plant.

Cutting off the damaged leaves is the best way to deal with it. However, there are other solutions to get rid of each pest of these.

  • You can use a solution of isopropyl alcohol to handle mealybugs. But make sure your solution isn’t powerful enough to burn the plant.
  • Scales can be wiped off with a water hose.
  • Slugs, on the other hand, can be eliminated by strewing rough surfaces around the plants’ base, such as gravel, broken eggshells, or coffee grounds.

Final Thoughts

Growing a Boston fern can be fairly easy if you provide them with the right environment because their key success lies in humidity and mild temperatures.

Boston ferns, whether indoors or out, like a cold, damp climate with indirect light. So, make sure to spritz them with water a couple of times a week to keep them fresh and healthy.

Additionally, these plants grow hardy in zones 9-11 and can’t tolerate temperatures below 40°F or above 95°F. Therefore, it’s better to shelter them in extreme conditions.