How to Plant, Grow, and Care for Frosty Ferns

Houseplants are a dime a dozen. There are thousands of species you can use, as our homes provide ideal conditions for tropical and temperate plants alike. So, why choose frosty ferns? If you’re looking for an untraditional houseplant with unique foliage, this is the plant for you.

Although most common as houseplants, frosty ferns make lovely ground covers for shaded gardens in warm climates. Their spreading tendrils let them creep onto bare soil, and they’re easily movable if you prefer they grow elsewhere.

No matter whether you grow frosty ferns in your home or garden, you’ll take delight in watching them mature. Abundant, decorative, and easy to grow, these fern cousins outshine poinsettias and amaryllis bulbs as the true winter stars. 

What Is It?

Frosty ferns are perennial plants in the spike moss family Selaginellaceae. Unlike true mosses, they grow roots from their fronds that help them spread into new areas. Frosty fern is a common name that refers to spike mosses with bright tips. 

Native Area

Growers often sell two different types of frosty fern: the variegated variety of Krauss’s spike moss, or Selaginella kraussiana ‘Variegata,’ and variegated spike moss Selaginella martensii. Other species and varieties may also have the name “frosty fern” if they have frosted tips. 

Krauss’s spike moss originates from Southern Africa, while variegated spike moss is native to Mexico and Central America. They grow beneath taller shrubs and trees, spreading roots and shoots throughout shaded grounds. 

Characteristics

Frosty ferns grow fern-like fronds with scaly foliage. The leaves resemble conifers like western red cedars or junipers, as each scale sprouts out from the previous one. The tips sprout bright white or yellow new growth that slowly matures dark green as it ages. 

Frosty ferns prefer warm, shady conditions year-round. They thrive in moist or wet soils in tropical forests, where they sprout aerial roots from their fronds that creep into the soil. Give them similar conditions in your home or garden, granting them fertile soil, warmth, shade, and regular water.

Planting

These fern cousins are available everywhere during the holiday season. Find them in plant nurseries, retailers, and garden centers. You can also browse shops online until you find the perfect plant of the size and variety you want. 

Growing from Spores

Although challenging, it’s possible to grow frosty ferns from spores. Find them online, or locate a mature plant and inspect the leaves’ undersides to see spores. Collect them when dry by scraping the fronds with a metal tool and placing a jar underneath to collect the spores. Store them in a cool, dark location until you’re ready to plant them.

Plant spores in small pots with potting soil. Surface sow them on top of the soil, mist them regularly, and move them near bright indirect light. You should start seeing seedlings after a few weeks or months. Practice patience, and help boost germination rates by placing a clear dome over the seedlings to trap humidity.

Transplanting

The best method for attaining a frosty fern is to find a young seedling and transplant it into a larger container when its roots outgrow the pot. This is more reliable than spore-starting, since spores are tiny and may take months to germinate.

Spike mosses have aerial roots that grow from their fronds. Take care to leave these intact while you remove the plant from its container. Prepare a new container with free-draining soil rich in organic matter. Outdoors, frosty ferns can sit in standing water for short periods. However, indoors they prefer moist, not soggy soil. 

Place the young plant’s rootball in the new container, then add soil around the roots so they sit below the surface. Spike mosses have shallow roots; give them a shallow container four to six inches deep. Grant them more width than depth so they have room to creep outwards.

How to Grow

These perennials need consistent humidity, moisture, and light to do their best. Give them the proper care they desire so they’ll reward you with leafy fronds for dozens of seasons. These fern-like plants have more care requirements than houseplants like snake or spider plants, but they’re well worth the time and energy.

Light

Indoors, frosty ferns like bright, indirect light. They grow best when they bask under indirect light, either from sunlight or grow lights. Place them near a window out of direct sunlight, and they’ll thrive year-round. Signs your plant receives too much light include whitening tips and yellow fronds.

Outdoors, these perennials like partial or full shade. They’ll tolerate dappled sunlight throughout the day under the shade of larger trees. Grow them outside if you live in USDA hardiness zones 9 through 12. Otherwise, consider placing them in containers throughout your home.

Water

These decorative houseplants appreciate consistent moisture throughout the growing season. They dislike sitting in standing water in pots, although they’ll tolerate short spells of sogginess outdoors. They also dislike hard water full of minerals and salts, so water them using filtered or bottled water. Consistent moisture is key to generating humidity, as these plants need high humidity levels to thrive. 

If your home is arid, consider using a humidifier to boost the humidity where your plant is growing. Other options include making a pebble tray with water. Fill a plant saucer with rocks, then fill it with water so that it sits below the pot’s drainage hole. The water will evaporate slowly, increasing ambient humidity around your fern-like houseplant. 

Soil

These tropical dwellers need loose, fertile soil to flourish indoors. Give them a potting soil mix rich in organic matter and drainage materials. Perlite or vermiculite particles create air pockets in the dirt, helping your plant’s roots breathe. Materials like compost or leaf mold feed the roots while adding structure to the soil. 

Outdoors, these fern-like plants tolerate growing in soils rich with clay or loam. Occasional flooding won’t harm them; it’ll saturate the soil with moisture for weeks. They’re also perfect for rock gardens in between rock cracks and crags. Let them root freely, and they’ll sprout along pebbles, rocks, and boulders. 

Fertilizing

Low feeders, these fern relatives need little fertilizer. They often face more harm from overfertilizing than underfertilizing. Their leaves start looking bleached throughout while their bright tips turn green. 

If your plant grows well without fertilizer, you may not need to add any. Your plant will benefit from some nutrients after it grows for a year in a container with fresh soil. Grant it a half dose of liquid organic fertilizer once every month or two during the growing season, and stop fertilizing from late fall through winter.

Maintenance

When happy, these plants spill out over their containers. Trim and remove the cuttings as they fall. These fronds grow leggy when they spill over the pot, and trimming them keeps the plant bushy and dense. Pot them up for new plants or recycle them in your compost pile. 

Frequent misting is beneficial for plants growing in dry rooms. Consider planting them in terrariums or lidded containers to keep them moist, warm, and humid.

Propagation

With aerial roots on all the leaves, a frosty fern is easy to propagate. You can grow cuttings anytime, while you can divide existing plants once they’re full and mature. Choose the method that works best for you, your plants, and your growing setup.

Cuttings

Take stem cuttings off of long fronds. It’s best if they have roots on the stem already, although rootless ones will still work. Bury the lower portion of the stems in containers with potting soil. Water them, then place them under bright, indirect light. 

Cuttings need extra humidity while they root. Ensure they have what they need by placing them under a clear humidity dome made of plastic or glass. The air may grow stale inside, so open it once a day to encourage airflow.

Cuttings should start forming roots after two weeks. Give them a few months in their containers until they have plenty of new growth and are well-rooted in their pots. Transplant them into larger containers, or plant them throughout your yard for a walkable ground cover.

Division

A potted plant eventually outgrows its pot. This is a sad reality for gardeners, although it doesn’t have to be sad! Dividing plants is one way to turn transplanting into an opportunity for propagation. When you’re ready to re-pot a frosty fern, remove it from its container and inspect the rootball.

You’ll want to free up the roots so they dangle downwards. Depending on the size of your plant, you may be able to turn a single specimen into two, three, four, or five new ones! Use a saw or knife to make sharp cuts in the rootball, dividing it into multiple pieces. Ensure each one has leaves, roots, and some soil. 

Place each division into a new container or bed with fresh soil, then water them well. Ensure they’re nice and humid while they transition into their new environments, and they’ll push out new growth in a few days. 

Popular Varieties

Although two main types of frosty ferns exist, there are other colorful spike moss varieties for the curious gardener. Once you choose your favorite, you’ll have a mother plant to make dozens of cuttings. Try one, or collect them all for an explosion of color and texture!

‘Variegata’

‘Variegata’ is a form of Krauss’s spike moss, Selaginella kraussiana. It grows low, between two and four inches tall, and sports frosty white tips on each frond. Most frosty plants you find will be a variety of this species, as it’s common in retailers and nurseries. ‘Variegata’ is the type for you if you’re looking for icy white tips and lush green fronds.

Variegated Spike Moss

This spike moss is of a different species in the same genus. Variegated spike moss, or Selaginella martensii, has yellowish-white growing tips instead of frosty white ones. It reaches a bit taller than Krauss’s spike moss, growing up to eight inches tall. It’s the perfect species for adding holiday charm to indoor rooms. 

‘Aurea’

Typical variegation is yellow instead of white. ‘Aurea’ is a type with this typical palette—its leaves are lime green, and the tips are sunshine yellow. It’s a variety of Krauss’s spike moss, meaning it stays low to the ground. Plant it in a pot with ‘Variegata’ for a bright blend of green, lime, white, and yellow.

‘Brownii’

‘Brownii’ is a special form of Krauss’s spike moss with lime green foliage throughout. It’s low-growing like ‘Aurea’ and ‘Variegata,’ and its roots perform well in shallow pots or beds. Use it as a filler or spiller in large containers amongst other warm-loving houseplants. 

Common Problems

Drought, root rot, and the occasional pest or two may affect your mossy plant while it grows. Because it demands more humidity and water than most other plants, a watchful eye and quick hand will help ensure you avoid these common problems before they appear.

Pests

Aphids, mealybugs, and spider mites may target your frosty fern. Keep it moist and under bright indirect light to keep it healthy, perky, and pest-resistant. You may have to take more invasive actions if the pesky insects remain on your plant. Start by rinsing off the leaves daily with strong streams of water. This should remove most pests after a week or two.

Use an organic oil or pesticide if pests endure the water treatment. Things like horticultural oil or soap work well, as does neem oil. Spray them outdoors in the morning or afternoon away from flowering plants that pollinators may visit. 

Diseases

Although not a disease, drying out can severely affect your frosty fern. Its fronds will turn yellow and brown before growing crunchy. Once crunchy they rarely recover. Low humidity causes issues like brown growing tips and weak growth. Avoid thirsty, dry plants with consistent watering and ample humidity.

Ironically, too much water causes growing issues! Root rot may occur if your ferny relative sits in soggy soil too long. Give it well-draining soil, and avoid letting it sit in a water-filled saucer unless there are pebbles underneath.