Shade-loving ferns are a good solution for yards that don’t get much sunlight. And ferns are by no means only for tropical or warm climates. Among the hardy ferns, autumn fern stands out because of its eye-catching seasonal foliage. In the spring, the newly emerging papery fronds are a bright coppery-red to orange-red. This stunning fall-like color, which gives the fern its common name, persists for several weeks. As the season progresses, the color of the glossy fronds changes to an equally bright green.
Autumn fern does not spread much so it’s suitable for small spaces. It makes a good groundcover for shady borders and woodland gardens, but it can also be grown in containers and, because of its smaller size, even as a houseplant.
|Common name||Autumn fern, Japanese shield fern, Japanese wood fern, copper shield fern|
|Botanical Name||Dryopteris erythrosora|
|Plant Type||Herbaceous perennial|
|Mature Size||18-24 in. tall, 18-24 in. spread|
|Soil Type||Moist, well-drained|
|Hardiness Zones||5-9 (USDA)|
Autumn Fern Care
The filigree look of autumn fern foliage is deceiving—this is an easy-to-grow fern with low maintenance requirements, which makes it an ideal groundcover. It is not a fast grower though; it takes five years for autumn fern to slowly spread to its mature size of about 2 feet.
Whether you need to water an established autumn fern depends on the amount of precipitation in your location. Applying a generous layer of mulch, on the other hand, is useful no matter where you live. It keeps the moisture in the soil during the summer and protects the plant from winter cold.
Autumn fern is relatively unbothered by wildlife. Rabbits and deer usually leave autumn fern alone.
Autumn fern needs to be planted in a shady location. Too much light is detrimental to its health and can sunburn it to the point of killing it.
The soil should be similar to conditions in the fern’s native woodland habitat in eastern Asia: acidic with a pH below 6.0, containing a high amount of organic matter, consistently moist but with good drainage.
Until it is established, during the first growing season, a newly planted autumn fern needs regular watering in the absence of rain. In climates with regular rainfall, watering is not necessary. In drier climates, or during dry spells or extended droughts, water the area around the plant slowly and deeply to keep the soil moist, ideally with a soaker hose.
Similar to all container plants, potted autumn ferns need frequent watering several times a week in hot weather to keep the soil moist at all times.
Temperature and Humidity
Autumn fern can grow in a fairly wide climate range; it tolerates both freezing winter weather and does well in moderately warm summer temperatures and high humidity. However, it does not do well in hot or dry weather, and it is especially vulnerable to drying winds that parch the soil.
In the lower range of its climate zone spectrum, in USDA zones 5 and 6, the foliage might die back during the winter but will bounce back in the spring.
Autumn fern that has been planted in soil high in organic matter only needs a springtime application of a complete all-purpose fertilizer.
Container plants need to be fertilized more often, about once a month during the growing season.
Types of Autumn Fern
- ‘Brilliance’ is a cultivar whose new fronds are a brighter coppery-red than the species. New colorful fronds appear during the entire growing season and gradually turn to deep green as they mature.
Autumn fern does not require pruning, in fact, when the old fronds wither over the winter, it is important to leave them on the plant. When they die down in early spring to make room for the new fronds, you can remove them for a neater appearance but be careful not to damage any new growth at the crown.
Propagating Autumn Fern
You can propagate autumn fern by division or by spores. Division is the easiest and therefore recommended method. You’ll need a mature specimen, one that is showing a bare center which is a sign that the plant needs to be divided to rejuvenate it.
- In the spring, when you see the first new fronds emerge, dig out the entire fern and all its roots (rhizomes) with a shovel.
- Separate it into smaller segments using pruners. Make sure that each segment has at least one growing tip with sprouts on it from which the fronds will emerge.
- Dig a hole slightly deeper than the root system. Add a few handfuls of organic matter and place the segment in the hole. Backfill with soil and gently press down on the soil. Water well and keep the new fern well-watered in the absence of rain until you see new growth and the plant is established.
A more involved and lengthier method is propagation from spores that you have collected yourself. This process can take 6 to 12 weeks.
Potting and Repotting Autumn Fern
You can also grow autumn fern in pots, as a houseplant or for a patio or balcony.
Select a pot, preferably clay or terracotta, with large drain holes. The pot needs to be tall and wide enough to accommodate the entire root system of the fern.
Because ferns prefer rich soil, rather than using just potting mix, fill it with a combination of all-purpose potting mix and compost. Water it well and keep the soil moist at all times. Especially when you keep your fern outdoors, you need to be diligent about watering and never let the soil dry out.
Repot the fern when it becomes root-bound, which is often indicated by smaller fronds.
When planted in garden soil, autumn fern does not need to any protection during the winter. As a potted plant, however, its roots are not sufficiently protected from winter chills. While there is no need to bring the containers indoors, provide additional insulation around the container. You can either place the container in a larger pot or box and fill the space with mulch or sand, or wrap the sides of the container with bubble wrap, or burlap and an additional layer of plastic wrap.
Common Pests & Plant Diseases
Common Problems with Autumn Fern
When the fronds of autumn fern become shriveled, brown, or discolored, the cause is usually sunburn. This can happen, and rather quickly within a few hours, with new plants that have been moved to a location with too much sunlight, or plants that were grown in a greenhouse and have not been properly hardened off. It can also happen to an established fern in your yard when you prune or cut down a tree or shrub nearby that used to cast shade on the location but is now more exposed to the sun.
Can autumn fern take full sun?
Autumn fern needs shade. It can grow in varying degrees of shade, from full shade or deep shade and partial shade to dappled sunlight but it does not tolerate full sun.
Is autumn fern a true fern?
Autumn fern reproduces via spores and has neither seeds nor flowers so it is a true fern.
Are autumn ferns evergreen?
In warm climates, autumn fern is an evergreen whereas in cooler climates, it is a semi-evergreen.