Japanese painted ferns (Athyrium niponicum) are colorful specimens that brighten the part shade to shady areas of the garden. Silvery fronds with a touch of blue and deep red stems make this fern stand out. Learning where to plant Japanese painted fern is key to the success of growing this attractive plant. When you’ve learned how to grow a Japanese painted fern, you’ll want to use it in all areas of the shade garden.
I. Appearance and CharacteristicsÂ
Athyrium niponicum, the Japanese painted fern, is a species of fern native to eastern Asia.
This species was redefined as a member of genus Anisocampium in 2011 based on phylogenetic analyses, but the genus has since been sunk into Athyrium.
This deciduous fern has a creeping rhizome and a tuft-shape array of fronds. The fronds are variable in length, generally 30 to 75 centimeters long but occasionally over a meter in length. They have alternately arranged, subdivided pinnae. The spore-bearing sori on the undersides of the fertile pinnae are variable in shape, being “oblong, hooked, J-shaped, or horseshoe-shaped”.
The Latin specific epithet niponicum means “relating to Japan (Nippon)”.
This is a commonly cultivated fern, especially A. niponicum var. pictum. It thrives in many kinds of shady garden conditions and produces thick colonies of gray-green fronds with reddish midribs. ‘Pictum’ is also considered to be a cultivar; varieties and cultivars are bred to achieve midribs in many shades of red.
A. niponicum var. pictum has gained the Royal Horticultural Society’s Award of Garden Merit. as has the cultivar ‘Silver Falls’.
II. How to Grow and Care
Sunlight
While Japanese painted fern is listed as being a plant for partial shade or full shade, the decision is often made for you based on where you live. At the more southerly end of its range, Japanese painted fern should be grown in full shade. Northerners have more choice in the matter. Still, the fact that the plant achieves its best color in the north if grown in partial shade more or less makes the decision on plant location for you.
Temperature and Humidity
The Japanese painted fern does best in moderate temperatures of 55 to 80 degrees Fahrenheit. It also prefers a moderate humidity level of 40 to 60 percent.
Watering
Keep the soil evenly moist (but not soggy). Otherwise, browning on the fronds will occur during the heat of summer.
Soil
An essential requirement in growing Japanese painted fern is soil with excellent drainage. Otherwise, the plant may suffer from root rot and fungal diseases.
Fertilizing
As long as you work organic soil amendments into its soil occasionally (including feedings of manure tea), additional fertilization should not be necessary. But if you prefer commercial fertilizers, apply a balanced fertilizer in spring, carefully following the instructions on the label.
Planting Instructions
Dig a hole a little deeper and wider than your potted Athyrium niponicum and add plenty of leaf mulch to the base of the planting hole to enrich the soil and add essential nutrients. Carefully tease your plant from its pot and gently loosen the roots before placing it into the hole with the crown just below soil level. Add some loosened garden soil around the sides of the plant before firming into place and watering generously.
Athyrium niponicum also grows well in pots – use a good quality compost with added leaf mould and ensure pot grown plants can drain freely but never dry out. Epimedium, Heuchera and Erigeron make great companions for container grown ferns.
Pruning
Pruning is not necessary to help the plant grow. Trimming away dead or diseased fronds is a good choice throughout the growing season. Feel free to prune the fern to keep a desired shape.
Propagation
Propagate by division or cuttings.
Divide clumps of mature plants into three to four divisions during the spring.
- Dig up the soil around the plant and carefully remove the entire root system.Â
- Shake the soil loose and locate the center of the root ball.
- Use gardening shears to cut the root at the base, dividing it into multiple sections.
- Large clumps may be planted directly into the ground, while smaller clumps should be placed in pots.
To propagate using cuttings, cut one or more fronds from a mature plant.
- The frond should measure at least 5″ or 6″ inches.
- Stick the end of the frond in rich, well-drained soil.Â
- Use small pots for the cuttings and place indoors in a shaded spot, receiving filtered sunlight.
- Keep the soil moist and allow the plant to overwinter indoors.Â
- In the spring, transplant small divided clumps or young plants from cuttings.Â
- Move them outdoors to their permanent spots in the garden or larger containers.
How to Grow from Seed
Japanese painted ferns don’t set seed; they travel by spores. Therefore, the best way to add Japanese painted ferns to your landscape is through division.
Overwintering
Japanese painted fern is a deciduous plant, so the fronds will die back in the winter. This is normal, and the fern should return with a robust fullness in the spring.
Pests and Diseases
Common Pests and Plant Diseases
Fortunately, Japanese painted ferns don’t have many pests to fight. Snails or slugs might nibble on the fronds. If they show up, remove them with your hands, then treat the fronds with neem oil. To prevent further pests, create a barrier around your plants with mulch or rocks. Rabbits are more of a problem, as they do love to eat the fronds. Deer, however, aren’t usually an issue.
If the fern is in too-moist soil, it can show signs of fungal issues or root rot. Avoid this by ensuring that the soil is well-draining.
Common ProblemsÂ
Even when grown in an area sheltered from bright sunlight, Japanese painted ferns lose some color once spring yields to summer (the fronds become greener). It is also natural for some fronds to brown up and die over time; cut off such dead fronds when you see them, for aesthetic purposes. Browning can also be the result of a lack of water; to help keep the soil from drying out, apply a mulch around the plants.
III. Uses and BenefitsÂ
Japanese painted fern is often grown in shaded gardens or near ponds and streams with shade from other plants.
The compact growth of the plant also works well as a border.
When growing near other plants, keep an eye on the spread of the roots.
IV. Types of Japanese Painted Ferns
There are numerous types of Japanese painted ferns, including:
- “Wildwood Twist”: As the name suggests, the fronds have a twisted appearance. This plant is a silvery gray color.
- “Burgundy Lace”: this plant has deep burgundy stems; the unique color is repeated in striations on the fronds.
- “Pictum”: This plant has an attractive combination of silver and red colors throughout the fronds.
