Ferns are among the oldest and toughest plants on Earth, with their origins tracing back nearly 400 million years. These prehistoric plants, once towering giants of primeval forests, evolved into the second most diverse group of vascular plants on Earth. Today’s ferns may not reach the colossal sizes of their ancestors, but their hardiness is still unquestionable. Among these, the Boston Fern emerges as one of the most popular and easy-to-grow ferns that can tolerate temperatures as low as 50°F (10°C).

Key takeaways

  • Boston Ferns prefer temperatures between 60°F to 75°F (15°C to 24°C), but they can tolerate cold weather down to 50°F (10°C).
  • These ferns love moisture, especially in hot, dry conditions. However, it’s important to balance this with good drainage to prevent root rot.
  • In colder months, reduce watering as ferns enter a dormant phase, but ensure the roots don’t dry out completely.

Ideal Temperature Range For Boston Fern

Boston Fern

Boston Ferns, known for their lush and arching fronds, have been a popular choice for both indoor and outdoor plants since Victorian times. While they can easily tolerate cold temperatures, it’s best to keep them in a comfortable temperature range of 60°F to 75°F.

When Is It Too Cold For Boston Fern?

Boston Ferns prefer a temperate climate, thriving best in environments where temperatures range between 60°F to 75°F (15°C to 24°C). Even though ferns are hardy by nature, unlike cactus, they cannot tolerate extreme cold. The lowest Boston Fern can withstand is 50°F (10°C).

When exposed to temperatures below 50°F (10°C), Boston Ferns begin to experience stress. The fronds may turn yellow and wilt, indicating discomfort. Prolonged exposure to cold can lead to more severe damage or even plant death. 

Potted Boston Ferns are vulnerable to cold damage, as their roots have less insulation from the frost. They can perish if the temperature drops below 45°F. Ferns planted in the ground, on the other hand, can withstand colder conditions of up to 30°F, as their roots are more protected by the soil. However, it’s important to note that while the roots may survive, the fern’s fronds and upper parts are likely to die to the cold.

Boston Ferns In High Temperature

On the flip side, Boston Ferns are just as sensitive to high temperatures as they are to the cold, particularly when these warmer conditions are paired with low humidity. When the temperature rises above 75°F (24°C), you might notice your Boston Ferns beginning to feel the strain. However, keeping them well-watered and in shaded areas can help your Boston Fern stay healthy. 

At 80°F – 90°F (24°C – 32°C) Boston Ferns may show more serious signs of stress, including browning at the tips of their fronds and an overall decline in their health. 

Care Tips For Boston Ferns

As a tropical plant, Boston ferns love humidity and moisture with indirect sunlight. To keep fern healthy, it’s important to keep the soil moist but avoid overwatering. Remember that well-drained soil is crucial to prevent root rot. 


Boston Ferns love water! While we’ve cautioned about overwatering, it’s rare for these ferns to get too much of it. They crave water, especially on hot summer days. In times of low humidity, it’s best to water them twice a day. 

These ferns prefer their soil to be moist but not drenched. A good rule of thumb to check their watering needs is to gently lift their pots. If the pot feels light, it’s likely time to give your fern a drink. On the other hand, a heavier pot usually indicates they have enough water.

Indoor Care

When growing Boston Ferns indoors, it’s important to mimic their natural humid environment. They thrive in high humidity, so consider placing them in a bathroom or kitchen where moisture levels are higher. 

If the air in your home is dry, especially during winter, using a humidifier can be beneficial. Position your fern in a spot with bright, indirect light. Direct sunlight can scorch their fronds, while too little light can hinder their growth.


During the colder months, ferns take a break from growing, which means you can safely cut back on watering compared to their needs in warmer conditions. However, it’s crucial to ensure that their roots don’t dry out completely. A practical way to monitor this is by placing a dish under the pot. This setup lets you easily see when it’s time to water your plants, keeping the moisture levels just right.

To further assist your ferns in conserving energy, consider giving them a bit of a trim. Removing dead fronds not only tidies up the plant but also helps it retain water by reducing moisture loss through the leaves. And for an added boost in creating an ideal environment, think about using a mist humidifier. This can help maintain a humid atmosphere in the room, providing your ferns with a little extra comfort during the drier, colder season.

3 Other Fern Types With Cold Tolerance

Boston Ferns can tolerate cold temperatures as low as 50°F (10°C). While this is already pretty impressive for a tropical fern, there are also other ferns that can also tolerate cold climates. 

Frosty Ferns

Frosty Ferns

Frosty Ferns, often mistaken for true ferns due to their fern-like appearance, are actually a type of clubmoss. They are renowned for their ability to tolerate cold temperatures, often surviving in conditions where other ferns may struggle. 

Frosty Ferns can endure temperatures as low as 20°F (-6°C), though they prefer to stay in the range of 60°F to 70°F (15°C to 21°C) for optimal growth. Their unique, frost-tipped fronds give them a distinctive appearance, especially in colder months, making them a favorite for winter gardens.

European Ferns

European Ferns

European Ferns, such as the Dryopteris genus, are well-adapted to cooler climates. These ferns are native to various parts of Europe and are known for their hardiness in cold weather. Some species within this group can withstand temperatures well below freezing, making them ideal for temperate to cold regions. 

European Ferns typically feature robust, upright fronds and can be a striking addition to any garden, especially in areas where winter temperatures can be challenging for less hardy plants.

Tropical Ferns

Tropical Ferns

Contrary to what their name suggests, some Tropical Ferns exhibit a surprising level of cold tolerance. While they thrive in warm, humid environments, certain species have adapted to cooler temperatures. 

These ferns can often withstand brief periods of cold, down to about 50°F (10°C), without significant damage. However, they generally do not tolerate frost and should be protected or moved indoors during colder months. Their ability to adapt to a range of temperatures makes them versatile choices for indoor and outdoor gardening.


  1. Can I put my Boston fern outside?

    Yes, you can put your Boston Fern outside, but it's important to consider the climate and weather conditions. Boston Ferns prefers temperatures between 60°F and 75°F (15°C to 24°C). They enjoy high humidity and indirect sunlight. If you live in an area with mild temperatures and not too much direct sun, your fern can do well outdoors. 

  2. When should I bring my Boston fern inside?

    You should bring your Boston Fern inside when the temperature starts to drop below 50°F (10°C). These ferns are sensitive to cold and cannot withstand frost. Before the first signs of frost in the fall, it's advisable to move your fern indoors to a bright, humid spot. This transition should be gradual to prevent shock from the sudden change in the environment.

  3. How do you keep ferns alive in the cold?

    To keep ferns alive in the cold, especially during winter, it's crucial to maintain a stable and suitable environment indoors. Keep the fern in a cool, well-lit room, away from direct heat sources. Ensure the humidity level is high enough – using a humidifier can help. Water the plant less frequently than in the summer, but don't let the soil dry out completely. Trimming dead fronds can also help the plant conserve energy.

  4. Can Boston ferns survive in air-conditioned rooms?

    Boston Ferns can survive in air-conditioned rooms, but there are some considerations to keep in mind. Air conditioning can reduce humidity levels, which Boston Ferns rely on. You can increase humidity around the plant by misting it regularly, placing a humidifier nearby, or using a pebble tray with water under the plant pot. Also, ensure the fern isn't in the direct path of cold air from the air conditioner, as sudden temperature drops can be harmful.


We call him our tech nerd. You will enjoy his articles about AI, electronics, technology, etc. But more importantly, Hai Long is a passionate lover of plant life, forests, and ecosystems. He has no formal qualifications in the field, but we found him a great match for our blog. Hai Long has always been intrigued by the complexity of ecosystems, particularly forests. Over the years, he has explored various terrains, developing an understanding of the interactions between plants and their surroundings. Hai Long chose to join the Tenereteam blog to share his enthusiasm and knowledge with others.

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