How to Plant, Grow, and Care for Ostrich Ferns

Close your eyes and imagine what a typical fern looks like. Chances are, you’ve imagined something close to the ostrich fern. This fern is widespread across North America and is one of the most common garden ferns.

They are not only popular amongst gardeners. They are also famous among foragers for their delectable fiddleheads that emerge in spring, with a flavor often compared to asparagus. Just be sure you’re actually dealing with the correct species before harvesting, as many fern fiddleheads are toxic.

This species is essential to shade gardens and is easy to grow and remarkably low-maintenance. Read on to find out how to best grow and care for ostrich ferns.  

What Is It?

Scientifically known as Matteuccia struthiopteris, this classic garden fern is named after its fluffy green fronds that look like grand ostrich feathers.

As a North American native plant (it’s also found in parts of Europe and Asia), it grows incredibly well in gardens across the US, dispelling any hard-to-grow reputation other ferns may have.

Ostrich ferns are planted for their beautiful fronds and ability to grow in shade, easily filling empty gaps under trees or garden structures. Thanks to their long history, they contribute an ancient woodland look, with ancestors over 300 million years old. In fact, they are known as ‘dinosaur plants’ in my house thanks to this historical significance.

But planting them doesn’t only add ornamental value to your garden. This species is also among the few that produce edible fiddleheads – often considered a culinary delicacy and a great ingredient to play with in the kitchen. These plants are widespread across North America and popular with foragers.

Characteristics

Ostrich fern fronds can reach impressive heights of up to 6 feet when mature. These fronds emerge in a circular pattern, gently arching outwards and creating a lush, full appearance.

Sterile fronds have a bright green hue and provide the backdrop for the shorter fertile fronds that may emerge in spring in some plants. When mature, these fertile counterparts are easily distinguishable from sterile fronds in size and unique color and take on a deep, almost chocolatey brown hue. Fertile fronds will release spores, while sterile fronds are those harvested early as fiddleheads.

In fall, green fronds transform into a golden brown as temperatures dip. The fern will shed its sterile fronds during colder months (fertile fronds will remain on the plant), only to return the following season with bright green fiddleheads.

Although these plants can spread via spores, they reproduce far more rapidly by underground rhizomes. Their spread can become quite aggressive if not controlled, so it’s important to remember when deciding on a planting location.

Planting

Fall before frost is usually the best time to plant, giving the roots plenty of time to establish. But you can also plant in early spring, just before the new growth begins. As they prefer cooler temperatures over warm weather, planting in cooler seasons helps limit root stress.

While these ferns are adaptable, they thrive best in partial to full shade. A location under the canopy of trees or placement on the shaded side of garden structures or your home is often ideal. Not only does this protect them from the scorching midday sun, but it also replicates the cool, moist conditions they prefer.

When you’re ready to plant, dig a hole about twice the size of the container and amend the soil with compost to improve health and retain moisture. Place the fern in the hole and keep the crown level or just above the soil surface, as burying the crown too deeply can lead to rot.

Fill in any remaining gaps and press around the base gently to remove large air pockets. Water immediately after planting, settling the soil around the roots. If you’re planting multiple ferns, spacing about 2 feet between each is recommended to account for their spread.

Planting In Containers

For those limited by space, container planting is also an option.

The chosen container should be very deep and wide to make space for the extensive root system and to balance the tall fronds. Also, ensure the container has adequate drainage holes to prevent waterlogging and potential rot.

Fill the pot with a mix of potting soil and compost to retain plenty of moisture (containers dry out quickly). The same planting rule applies – the crown should sit level with the soil’s surface.

Given their love for moisture, it’s crucial to monitor the soil in containers regularly, ensuring it remains consistently moist but not soggy. You will also need to repot and divide quite often due to their quick spread.

How to Grow

If you plant your ostrich ferns in the right place, they largely take care of themselves. Some extra watering may be needed in dry areas, but beyond that, these plants won’t give you any trouble. The most important part of maintenance is actually controlling their spread thanks to their vigorous growth.

Light

Ostrich ferns are quite particular regarding sunlight due to their woodland native habitats. Like other ferns, these plants have evolved to thrive in environments where sunlight filters through a dense canopy. Partial to full shade is preferred to match these native conditions.

Direct sunlight, especially during midday peak hours, can quickly dry the fronds and potentially kill the plant. The intense rays scorch the fronds, causing them to brown and wilt within a few hours.

If you’re planting outdoors, consider locations shielded from intense afternoon sun, either behind taller plants or under the shade of a tree. In containers, keep them undercover and away from direct sun.

Deep shade will slow growth, which is helpful for managing their rapid spread. However, it will also affect overall health and frond color. Partial shade is the sweet spot for these ferns.

Water

Originating from forest floors where the soil remains consistently damp, ostrich ferns love moisture. They grow best with consistent access to water rather than drying out completely. This also keeps the roots cool, especially in warmer climates where these plants may struggle.

However, despite their love for water, there is such a thing as too much. Prolonged exposure to waterlogged conditions can lead to root rot, damaging the crown and killing the rest of the plant. While it’s essential to ensure the soil remains moist, it’s equally crucial to ensure it’s well-draining.

During the warmer months, these ferns appreciate a deep watering whenever the top inch or two of the soil feels dry to the touch. As autumn approaches and growth slows, you can reduce the frequency, but never let the soil dry out completely.

Ferns in containers will need water more often as the soil dries out much quicker. Test the soil every few days to stop the roots from drying out.

Soil

In forest habitats, soil is rich in organic matter thanks to the layers of debris that build up over time.  This rich medium provides essential nutrients and retains moisture, ensuring the fern’s roots remain hydrated without becoming waterlogged.

The ideal soil for ostrich ferns is a rich loam with plenty of compost mixed in to replicate these conditions. Sandy soil will dry out too quickly, and heavy clay may lead to crown rot. Amending either soil type with plenty of high-quality compost will improve conditions to create the soil environment they love.

Drainage is essential, especially in low-lying areas where water tends to collect in your garden. A well-draining soil ensures excess water can quickly drain away while retaining enough moisture to keep the roots happy.

For potted ferns, a mix of potting soil, compost, and a bit of bark for extra drainage will provide the ideal conditions for root growth.

Temperature and Humidity

Despite its delicate look, this plant is surprisingly resilient with its temperature requirements. They are most comfortable in USDA Zones 3 to 7, preferring cool and mild climates over warm ones. However, in a heavily shaded forest (such as the redwood forests in northern California), they can grow all the way up to zone 9.

During the peak of summer, it’s essential to shield them from scorching heat, especially in zones at the higher end of their preferred range. They can withstand colder temperatures (even those that dip below freezing) and bounce back again once spring emerges.

High humidity levels, mimicking their native forest conditions, are ideal for healthy, long fronds. However, they are generally happy with any humidity level above 30%. Keeping the soil consistently moist will also help boost humidity around the plant when the air is dry.

Fertilizing

These ferns are considered low-maintenance, and this extends to their feeding requirements. If you’ve planted in rich soil amended with compost to boost nutrients, you won’t need to worry about fertilizing. A top-up of compost every few months will help maintain levels and boost soil health, keeping the ferns happy year-round.

If you want to boost them, you can add a slow-release fertilizer to the soil once per year in early spring. Don’t overdo it – overfertilizing can actually stunt growth rather than improving it. Rather, stick to upping nutrients with organic matter to keep the roots happy.

Maintenance

During their first year, ostrich ferns will benefit from a protective layer of mulch to retain soil moisture and provide a steady supply of nutrients as the mulch breaks down. Once established in their new homes, they won’t need as much attention unless temperatures increase or rain dips unusually.

As the colder months loom and the fronds start to change color, you can leave them to die back naturally or trim them to tidy the garden. Removing the fronds in late winter or early spring also clears the way for new growth, ensuring your fern looks its best as the weather warms.

This keeps the plant looking tidy and helps prevent pests and fungal diseases that might take advantage and settle in over the cooler months.

The most important maintenance task to complete is managing their spread. The rhizomes spread quickly underground, creating new fern clusters in unexpected places. While this can be useful to fill empty spaces, it can quickly overtake other areas of the garden. Consider occasionally checking the spread and dividing the ferns to manage their growth.

Propagation

This species spreads quickly on its own. But if you want to move plants to containers or another part of your garden, propagating is easy.

Division is the most common method of propagation for these ferns. This is best done in early spring or fall to take advantage of mild temperatures and extra moisture, ensuring the young plants get a strong start.

To start, carefully lift the mature plant using a spade or fork, taking care not to damage the root system. Remove the plant completely to get a closer look at the rhizome. Using a sharp, sanitized knife or shears, gently separate out sections of the rhizome, ensuring each division has a healthy set of roots attached.

Once you have your divisions, it’s time to plant them in their new homes. Follow the previous planting instructions as you would when purchasing a new plant. With the right care, you’ll soon see the fern’s signature fronds unfurling, indicating the roots have become established.

Propagating From Spores

Division is the easiest propagation method, but it’s not the only one. You can also propagate ferns from spores if you want to try a little garden experiment. While this method is more intricate than division, the excitement of raising a fern from a tiny spore is incredibly rewarding.

Start by identifying the fertile fronds – typically darker, shorter, and more tightly curled than the sterile ones. As they mature, they will produce clusters of spore cases. To collect, place a mature frond in a paper bag. When the frond dries out, you’ll notice a fine, dusty residue inside – these are the spores.

Next, prepare a container by filling the base with perlite, followed by peat and seedling mix. Moisten the mix by watering it with boiling water to sterilize it, leaving to cool before planting. Gently sprinkle the collected spores over the prepared growing medium, ensuring they’re evenly spread.

Cover the tray with a clear plastic bag, creating a mini greenhouse, and place the tray in a location with bright, indirect light. Ensure the medium remains consistently moist but not waterlogged. The spores will germinate over the next several weeks, forming a greenish carpet called prothallia.

Once the prothallia develop tiny fern-like structures, they’re ready to be transplanted. Using a sterilized tool, gently lift and transplant them into individual pots to continue growing.

Harvesting

Early spring’s young, coiled fronds are an exciting sight and a delectable treat prime for harvesting. If you are 100% sure that your ferns are indeed Matteuccia struthiopteris, you have a bounty of delicious produce awaiting you when these appear!

Readied with gloves and a sharp knife or scissors, look for young fronds that are tightly coiled. Ensure they are bright green, firm, and no more than six inches tall. Gently cut them close to the ground, but be mindful not to harvest all from a single plant. Leaving a majority ensures the fern continues to grow and thrive.

Once you’ve gathered your fiddleheads, clean them thoroughly. Rinse them under cold water, gently rubbing to remove any debris. It’s common to find small insects, so a thorough cleaning is crucial. You can also soak them in cold water, allowing lingering pests to float to the surface.

After harvesting, you’re ready to cook. Fiddleheads should never be consumed raw – boil them for at least 15 minutes or steam for 10 to 20 minutes before cooking. After boiling, they are best sautéed in butter with garlic and used as a side.

Their flavor, often compared to asparagus, pairs wonderfully with lemon zest or even a splash of white wine. They also make a delightful addition to pasta, paired with other fresh spring veggies.

Before consuming any fiddleheads – foraged or harvested from the garden – it’s crucial to be absolutely certain of their identification. Other fern varieties have toxic fiddleheads that cannot be eaten, so be sure of what you’ve got before cooking.

Common Problems

Ostrich ferns are usually problem-free, resistant to many garden pests, and grow well without fuss. The most common problem you’ll face is controlling their spread, but there are also a few other issues to look out for.

Vigorous Spread

These ferns are known for their enthusiastic growth, spreading via rhizomes beneath the soil. While this can create a lush woodland look, it might also overshadow other plants.

Regularly inspect the perimeter of the planting area and consider installing barriers or borders to contain their spread. If they do grow beyond their designated area, division and transplanting can help manage their growth.

Crispy Leaves

If the fronds become brown and crispy, particularly around the edges, it’s usually a sign of insufficient moisture or excessive sunlight.

These ferns thrive in consistently damp soil and shaded environments. Ensure they’re watered regularly, especially during dry spells, and consider relocating them if they’re exposed to too much direct sunlight.

Pests

While these plants aren’t pest-prone, you may encounter slugs and snails, especially on young fronds. Regularly inspect your ferns during the evening when these pests are most active. Consider using organic slug and snail baits or creating your own beer trap to control these pests.

Diseases

Fungal diseases are possible, especially when the environment is excessively damp and lacks proper air circulation. Ensure the soil is not waterlogged or soggy, and regularly prune dead or diseased fronds to limit risk.

Frequently Asked Questions