Japanese painted fern is a lot different from the plain green ferns that many gardeners are most familiar with, such as the interrupted fern (Osmunda claytoniana). True to its name, Japanese painted fern is more colorful, offering triangular, silvery leaves (called "fronds," technically) that sport an arching habit. As if that were not exciting enough, they also have grayish-green in them, as well as purplish midribs, making them variegated ferns.
|Botanical Name||Athyrium niponicum; cultivar/variety discussed here is pictum, but other choices also exist|
|Common Name||Japanese painted fern|
|Plant Type||Deciduous fern|
|Mature Size||About 18 inches tall and wide|
|Sun Exposure||Partial shade to full shade|
|Soil Type||Well-drained, humusy, and kept evenly moist|
|Soil pH||Neutral to very acidic or slightly alkaline|
|Bloom Time||Non-flowering; ferns are an ancient group of plants that reproduce via spores|
|Hardiness Zones||3 to 8|
|Native Area||Eastern Asia|
How to Grow Japanese Painted Ferns
Japanese painted fern is one of the easiest plants to grow. It tolerates two conditions that many plants are highly intolerant of:
- Very acidic soil
- Deep shade
The main things to remember in growing it are that:
- You must protect the colorful fronds for which this foliage plant is grown from exposure to the hot afternoon sun. Such exposure will burn them.
- Work amendments into the soil before planting to feed your Japanese painted fern and help get it established.
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.
Japanese painted ferns spread via rhizomes and may even naturalize over time. Happily, for the gardener who demands low-maintenance, this spreading occurs only very gradually. But the spreading nature of the plants does allow you to divide them (spring is best) and multiply the number of them available for use elsewhere in your landscaping.
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.
An essential requirement in growing Japanese painted fern is a soil with excellent drainage. Otherwise, the plant may suffer from root rot and fungal diseases.
Keep the soil evenly moist (but not soggy). Otherwise, browning on the fronds will occur during the heat of summer.
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.
Uses for Japanese Painted Fern in the Landscape
Let their need for shade guide you when deciding on how to use Japanese painted ferns in your landscape. These shade-loving plants are excellent:
- For use in woodland gardens
- As edging plants, perhaps along a path through a shaded area
- As smaller plants to grow among the trees and shrubs that you have in your border plantings
- For planting around water features located in shady spots
- To control erosion on hillsides covered with shade
Some other shade plants that make excellent companions for Japanese painted fern include:
- Coral bells (Heuchera sanguinea): Varieties with burgundy leaves combine especially well with Japanese painted fern.
- Hosta spp. (particularly types with blue leaves, such as Halcyon)