<em>Dryopteris</em>: planting, cultivation and care

botany

Dryopteris are ferns that form clumps of fairly large, divided fronds. They make up a fairly large group, with about 300 species. They occur mainly in temperate zones of Northern Hemisphere. Greatest diversity is observed in East Asia, although they are also found on other continents such as Europe and North America. Best known is Dryopteris filix-mas, also called Male fern, which occurs wild in France.

Like many ferns, Dryopteris grow mainly in forest, on fresh, humus-bearing soil. They are also found on riverbanks and sometimes in rocky areas. In the garden, they should therefore be grown in shade or partial shade, in a cool or moist environment.

Ferns are primitive, very ancient plants. They belong to Pteridophyta, together with horsetails and selaginellas. Dryopteris gave their name to family Dryopteridaceae (about 1,870 species), which also includes Polystichum, another group of ferns grown for ornamental interest.

Etymologically, name Dryopteris comes from Greek dryas: oak, and pteris: fern, because some Dryopteris grow in oak woods. This can be confusing with another fern species, Gymnocarpium dryopteris, also present in French forests but quite different from true Dryopteris.

Dryopteris filix-mas: Botanical illustration

Dryopteris form clumps from which divided fronds emerge, creating a flared effect. Fronds therefore arise directly from this stump and are neatly arranged in a crown. Most Dryopteris measure between 60 cm and 1.50 m in height. Dryopteris goldieana, Dryopteris affinis and Dryopteris filix-mas are among the largest (between 1 m and 1.50 m), while Dryopteris marginalis, Dryopteris cycadina and Dryopteris sieboldii are much smaller. Ferns have a distinctive silhouette: slender, light and graphic.

Dryopteris have short rhizomes from which fronds develop. These are underground stems that grow horizontally or erect and develop slowly.

Ferns have a particular mode of reproduction: they form neither flowers nor seeds. They produce, usually on the underside of fronds, spores for reproduction. Spores are enclosed in sporangia, which open at ripeness; sporangia are themselves gathered in sori. In Dryopteris, these sori, or clusters of sporangia, are protected by a small kidney‑shaped membrane (indusium). Spores are released and drift away like dust. They are carried by wind and can travel far.

This mode of reproduction depends on water. To allow emergence of new ferns, spores are dispersed and then give rise to intermediate organisms: prothalli, tiny moss-like organisms that bear the reproductive organs. They produce male gametes which, thanks to water, can move to fertilise female gametes. Once fertilisation has occurred, a new seedling will develop on the prothallus.

Ferns therefore need water to reproduce, which explains why they are so often found in wet areas, on riverbanks or lakeshores.

On underside of fronds, sori can be seen: clusters of sporangia which, when ripe, open and release tiny spores, enabling ferns to multiply. Here, Dryopteris erythrosora (photo KENPEI) and Dryopteris wallichiana (photo Forest and Kim Starr)

Leaves of ferns are called fronds and have the peculiarity of being rolled into a crozier when they appear in spring. Emergence of croziers in spring is a real spectacle! They take a very decorative spiralled shape, generally covered with brown scales, and slowly unfurl to reveal majestic fronds. Dryopteris fronds are large, fairly broad at the base and tapered at the tip.

Most Dryopteris have fronds twice divided. Fronds are divided into pinnae on each side of a central axis, and these pinnae are themselves divided into pinnules. The central axis is called the axis. In Dryopteris wallichiana, it has a beautiful brown colour, bringing out the glossy green of the fronds. In Dryopteris, pinnules are fairly broad and rounded.

Very different from other species, Dryopteris sieboldii bears fronds only once divided. They consist of broad, entire pinnae, matt blue‑green in colour.

There are horticultural varieties whose fronds take surprising shapes! They are generally cristate, with twisted and forked pinnae at the tip. This is the case with Dryopteris affinis ‘Cristata’. Likewise, Dryopteris ‘Linearis Polydactyla’ is notable for its very fine, somewhat irregular pinnae. They give the plant a particularly light, airy, almost transparent appearance.

Dryopteris erythrosora stands out for its superb fronds with coppery hues when young. Dryopteris lepidopoda also has coloured fronds, coppery when young. In many species, young fronds are paler, pale green or even yellow when they appear in spring, then become darker green.

Croziers of Dryopteris wallichiana (photo Forest and Kim Starr), young fronds of Dryopteris affinis (photo Len Worthington), and coppery fronds of Dryopteris erythrosora

Some Dryopteris have a rather compact, massive habit, such as Dryopteris wallichiana, which bears glossy, very regular fronds. Others, like Dryopteris erythrosora, are much more delicate and light. This is also the case with Dryopteris ‘Linearis Polydactyla’, with very fine, airy fronds.

Depending on species, fronds may be deciduous or evergreen: they either remain in place over winter or wither and reappear in spring. Thus, Dryopteris erythrosora and Dryopteris affinis are evergreen, while Dryopteris filix-mas and Dryopteris goldieana are deciduous. For many species, leaf persistence also depends on climate: some are deciduous if winter is cold, but retain foliage under milder climates.

Main varieties of Dryopteris

Most popular varieties

Our favourite varieties

Other varieties to discover

Dryopteris erythrosora - Copper Fern

A fern notable for the colour of its fronds: first orangey-pink when young, then dark green. It has a beautiful triangular shape and is also evergreen!

• Height at maturity 70 cm

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Dryopteris wallichiana - Wood Fern

Native to Asia, Dryopteris wallichiana is a large fern with evergreen or semi-evergreen fronds. It has a black rachis (central axis) that provides a striking contrast with the glossy green fronds. It received RHS Award of Garden Merit.

• Height at maturity 1,50 m

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Dryopteris filix-mas - Male Fern

This is a male fern, a species found wild in France. It forms tufts of well-developed, twice-divided green fronds. It is particularly robust.

• Height at maturity 1 m

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Dryopteris cycadina - Black Wood Fern

Native to Asia, this species bears beautiful soft green, delicate foliage with a scaly petiole. Its foliage is evergreen in mild climate but dies back if temperatures are harsh in winter. It received RHS Award of Garden Merit.

• Height at maturity 80 cm

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Dryopteris goldieana - Giant wood fern

Dryopteris goldieana is a fern native to North America (USA, Canada) with pale pastel green, deciduous foliage. Large in size, it can reach 1.50 m in height! It easily finds a place in exotic or tropical-style gardens.

• Height at maturity 1,50 m

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Dryopteris affinis - Scaly Male Fern

This is an imposing fern with mid-green fronds, lighter when young, resembling male fern (Dryopteris filix-mas). Its foliage is evergreen and therefore remains ornamental even in winter!

• Height at maturity 1,20 m

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Dryopteris sieboldii - Japanese Fern

This is an unusual fern originating from China and Japan with fronds divided into very broad pinnae of bluish-green colour. They are thick and slightly undulate at the margins. This fern grows fairly slowly.

• Flowering time February
• Height at maturity 60 cm

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Dryopteris filix-mas Linearis Polydactyla - Male Fern

This is a variety of male fern with very fine fronds made up of narrow pinnae and pinnules. This gives it a vapoury, very light silhouette and creates a degree of transparency.

• Height at maturity 70 cm

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Dryopteris affinis Cristata - Scaly Male Fern

This variety forms a tuft with nicely arching fronds, but is especially striking for its cristate fronds: the tip of the pinnae is forked, dividing into several segments! It is also known under the variety name 'Cristata The King'.

• Flowering time February
• Height at maturity 90 cm

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Planting

Where to plant?

Like most ferns, Dryopteris need a cool, shaded position! Place them in woodland or at the foot of trees. Avoid very dense shade. They appreciate bright locations sheltered from scorching sun. Likewise, exposure depends on your location: Dryopteris should be grown in shade if you live in the Mediterranean basin, whereas in northern France you can more easily install them in full sun. In all cases, preferably choose a position sheltered from wind. However, Dryopteris are very hardy and do not need protection in winter.

Dryopteris prefer light, humus-rich soils. The ideal is woodland soil, as found in forest. Feel free to add well-rotted compost to enrich the soil and improve its structure. This promotes humus formation, lightens the soil while improving retention of water and mineral nutrients. Dryopteris also prefer acidic or neutral substrates.

Ferns are ideal for creating a woodland garden with a fairly natural style. They are perfect for dressing the base of trees and bushes, and their spreading foliage brings a lovely sense of volume and texture to borders! As they also prefer cool, relatively moist spots, you can plant them near a pond or stream. They can also find a place in a shady rock garden. For this use, we particularly recommend Dryopteris sieboldii.

When to plant?

You can plant Dryopteris in autumn, around October, or in spring, around April. The most important thing is to avoid periods of frost or extreme heat.

How to plant?

Dryopteris are light, delicate young plants that add a lush effect to the garden. Feel free to plant them in groups to achieve a strong mass effect. They can form a superb green setting that showcases other blooms.

1. Once you have found the ideal spot for your Dryopteris, place the rootball in a basin filled with water. This will help the young plant establish and aid subsequent watering.
2. While it soaks, dig a planting hole about twice the size of the rootball.
3. Add well-rotted compost to enrich the soil.
4. Plant your Dryopteris.
5. Replace the soil around it, then water generously.
6. Apply mulch around your fern. You can use, for example, BRF or dry fronds. This helps prevent the soil from drying out too quickly, and the decomposition of the mulch will enrich the soil with humus. It also limits weed growth.

Dryopteris can also adapt to container planting in pots or tubs. Choose a large container with drainage holes in the base. Place a layer of clay balls or gravel to prevent waterlogging. Then add potting compost, if possible mixed with heather soil. Place the fern, fill in with the substrate then water generously. Position the pot in a shaded spot.

Dryopteris wallichiana (photo David Wright)

Care

Dryopteris requires very little maintenance. It is a plant that does quite well on its own, without intervention. Moreover, it is rarely affected by pests or diseases. However, if you grow it in a pot, it will need a little more care, notably regular watering. Similarly, if you plant it in open ground, during the year of planting, we recommend watering to prevent it suffering from drought while it becomes established. Thereafter, Dryopteris will be more tolerant of drought.

You can add a little compost around your Dryopteris each spring to feed the soil. You can also renew the mulch by placing some around the stump from time to time. Use, for example, ramial chipped wood, pine bark or dried fronds. Spread it well around the plant, avoiding placing any on the crown of fronds.

If the species you are growing is deciduous, cut away dried fronds in early spring for aesthetic reasons and to encourage development of new fronds.

Discover our video tips on pruning ferns:

Propagation

Sowing spores

Dryopteris, like other ferns, do not produce seeds but spores that can be harvested and sown! However, this operation is more delicate than a standard sowing, as particular conditions must be observed. Sowing must be carried out on a sterile, moist substrate, in a confined medium.

1. Check undersides of fronds to spot spores. When mature, they are brown and shed naturally. Cut a frond fragment bearing spores and place it in a paper envelope. As it dries, the spores will be released and form a fine brown dust.
2. Then, to sow them, take a clean transparent container, plastic or glass.
3. Fill it with potting compost mixed with a little sand. Then moisten it.
4. Sterilise the substrate by placing it in a microwave oven for 10 minutes.
5. You can then scatter the spores over the surface of the substrate.
6. Place a transparent lid on the container (or, if unavailable, cling film), to maintain a confined, humid medium.
7. Place your sowing in a bright spot, out of direct sunlight.
8. Now all that’s left is to wait!
9. As soon as young fronds appear, you can remove the lid.

For more information and advice on sowing fern spores, discover our dedicated factsheet.

Dividing clumps

Dryopteris can also be propagated by dividing clumps in spring or autumn. This is a faster and easier technique than sowing spores, provided you have well-developed young plants. Choose a large, well-formed clump, then carefully lift it from the ground. Remove excess soil if necessary. Divide the clump by cutting the stump with a knife, ensuring that each fragment has fronds and roots. Make a clean, neat cut. Immediately replant the fragments in a new location or in pots, then water generously.

Association

As they grow naturally in cool, shaded conditions, Dryopteris will thrive in a woodland garden, sheltered from the sun by large trees and bushes. You can pair them with Solomon’s seal, sweet woodruff, Lamium, Brunnera, Geranium nodosum… You will achieve a very natural effect that will evoke a true woodland walk!

Dryopteris integrate perfectly into woodland gardens, creating a very natural atmosphere! Dryopteris affinis (photo MPF), Lamium maculatum, Polygonatum multiflorum (photo Markus Hagenlocher), Hosta ‘Emily Dickinson’, and Geranium nodosum ‘Le Clos du Coudray’

Dryopteris will also find a place in a shaded rockery. Choose in particular Dryopteris sieboldii, which has fronds divided into broad, entire pinnules, matte green. Place it with other small plants suited to rockeries, such as Ajuga reptans, Epimedium, Corydalis, Saxifrages, Tiarella… You can also include other ferns, such as Athyrium niponicum or hart’s-tongue.

You can easily incorporate them into a modern, graphic garden. Their triangular, divided fronds will provide a superb effect! Plant them alongside Japanese maples, horsetails, hostas, ophiopogons… Also take advantage of the very fine foliage of ornamental grasses (Carex, Stipa, etc.)

With their large, lush-looking fronds, ferns are ideal for creating an exotic-style garden. Choose, for example, Dryopteris goldieana or Dryopteris erythrosora, for the beautiful coppery or golden tones their foliage takes on in spring. Plant them with tree ferns, palms, castor bean, Tetrapanax, bamboos, Hedychium, Colocasia… Also discover the superb Datisca cannabina, with finely dissected leaves. Create a jungle garden, with lush, very large foliage!

For a more delicate, romantic aspect, Dryopteris also have a place in cottage gardens. Their elegant, graceful fronds perfectly accompany flowering of delphiniums, hydrangeas, foxgloves, roses, astrantias… Favour delicate blooms in shades of blue–mauve–white. They will be highlighted by the generous foliage of ferns!

Dryopteris affinis and Iris foetidissima

For more ideas and inspiration, discover our advice sheet: « Ferns: 9 easy pairing ideas for success! »