Ferns are loved for their feathery fronds and timeless charm, but when cold weather arrives, many gardeners start to wonder how to keep them alive.
Some ferns are hardy enough to survive outdoors with a little protection, while others, like Boston ferns, need to come inside when frost threatens.
Learning how to overwinter ferns properly means you’ll enjoy their beauty year after year instead of treating them as seasonal plants.
Here’s a step-by-step guide to help your ferns sail through winter healthy and strong.
Know Your Fern Type First
Not all ferns need the same winter care.
Hardy ferns like lady ferns or ostrich ferns can usually survive cold temperatures in the ground with a good mulch layer.
Tender ferns, including Boston ferns, Kimberly Queen, and staghorn ferns, won’t tolerate frost and must be brought indoors.
Identifying your fern type helps you decide whether to prepare it for outdoor dormancy or treat it as a houseplant during winter.
How to Overwinter Outdoor Ferns
If your fern is planted in the ground and is hardy to your USDA zone, you can let it rest outdoors.
After the first frost, cut back dead fronds to a few inches above the soil.
Then, cover the crown with 2-4 inches of mulch, straw, or leaves to insulate against temperature swings.
In early spring, remove the mulch to allow new growth to emerge.
Don’t water heavily during dormancy; nature usually provides enough moisture, but check occasionally if winters are unusually dry.
Bringing Potted Ferns Indoors
For tender ferns in containers, overwintering means bringing them inside before the first frost.
Give the plant a trim to remove damaged fronds and reduce size, making it easier to manage indoors.
Also, place the pot in a bright room with indirect sunlight, away from cold drafts or heating vents.
You should aim for temperatures between 60-75°F (15-24°C).
If your fern drops some fronds after moving inside, don’t panic, it’s adjusting to lower light and humidity.
Humidity Is the Secret
Ferns love humidity, and that’s often the biggest challenge indoors during winter.
Dry air from heating systems can cause browning tips and crispy fronds.
To help, mist your fern regularly, set it on a pebble tray filled with water, or use a small humidifier nearby.
Plus, grouping plants together can also create a more humid microclimate. Keeping the air moist is key to seeing your fern stay lush all winter.
Watering and Feeding in Winter
During the colder months, ferns slow down and don’t need as much water or fertilizer.
Water when the top inch of soil feels dry, but don’t let the pot sit in water. Overwatering in winter is a common cause of root rot.
Besides, fertilizer should be paused until spring, when the plant wakes up and starts pushing out fresh fronds again.
Final Thoughts
Overwintering ferns successfully comes down to knowing your type of fern and matching its needs.
Hardy ferns appreciate a protective mulch blanket outdoors, while tender ferns thrive indoors with extra humidity and gentle care.
With the right approach, your fern will be ready to burst back with fresh, vibrant fronds when spring returns.
