Athyrium

( ath - EER - ee - um )

At-A-Glance Information

The genus Athyrium, commonly called Lady Fern or Japanese Painted Fern, includes species that require full or partial shade and regular to ample water to perform well in the landscape. These are graceful ferns that brighten up shaded areas in the garden and woodland spaces. They spread over time by creeping rhizomes, and should be planted away from high-traffic areas to avoid unintentional damage to their foliage. Many species turn brown in frosty conditions, but will return the following spring with new growth. Use these ferns in mixed beds and borders in shade, in woodland or informal gardens, or in containers on patios or walkways. Take care when planting these ferns in the landscape, as plant parts are toxic to humans and pets if ingested.

Athyrium Species and Varietals

The genus Athyrium is a member of the plant family Athyriaceae and includes 180 distinct species. The best growing zones for these ferns vary depending on the species. For more information, see the descriptions below. To find your zone, click here: Zone Map.

Athyrium distentifolium (Alpine Lady Fern)
This species is native to a wide range in the Northern Hemisphere and produces light green fronds that reach between 12 and 28 inches long. This is a snow-tolerant species of fern and does well in USDA growing zones 3-9. These ferns do well on hillsides and rock gardens.

Athyrium filix-femina (Lady Fern, Common Lady-Fern, Subarctic Lady Fern, Tatting Fern)
This plant grows best in Sunset zones A1-A3, 1-9, and 14-24 (USDA zones 3-9) and is native to most of North America. It has a vigorous root system and is considered to be somewhat aggressive in the landscape, but is not invasive. Typically, they reach up to 4 feet tall and about 2-3 feet wide, and have finely divided fronds. Varieties of this species are outlined below.

'Frizelliae'
Gets to 8 inches tall and 1 foot wide, with balled-up fronds.

'Vernoniae Cristatum'
Gets 2.5 feet tall and wide, with crested and feathered fronds.

'Victoriae'
With 2-3 foot long fronds with crisscross leaflets.

Athyrium 'Ghost'
This species grows best in USDA hardiness zones 3-9 or Sunset growing zones 1-9 and 14-24. It is a popular hybrid variety, with upright growth reaching up to 2.5 feet tall. These ferns have a width of about 2 feet. Silvery gray fronds have showy purple midribs. Offspring of Athyrium nipponicum pictum and Athyrium filix-femina. Grows well in USDA zones 3-9.

Athyrium niponicum (Japanese Painted Fern, Japanese Silver Painted Fern, Painted Fern)
This species gets to 1-1.5 feet tall and wide, and creates a tight spreading clump of foliage. Leaves are purple at the base, lavender in the middle, and silvery green towards the tips. Grows best in USDA growing zones 3-8 (Sunset zones 1-9 and 14-24).

Athyrium otophorum (English Painted Fern, Eared Lady Fern, Limelight Lady Fern, Auriculate Lady Fern)
This species is native to China, Japan and Korea, and grows best in Sunset zones 3-9 and 14-24 (USDA hardiness zones 5-9). It produces greyish- green fronds with red to purple midribs. They open pale green. These are deciduous ferns that form tufts of foliage and are hardy down to 14 degrees Fahrenheit.

Caring for Athyrium

Take care when planting these ferns in the landscape, as plant parts are toxic to humans and pets if ingested. Athyrium, or Lady Ferns, are considered easy to care for and low-maintenance as long as their growing conditions are met. Plant in an area that is in full to partial shade, ensuring that during the warmest hours of the day (typically between 2 and 3 PM) that it is not in direct sunlight. They love rich, damp soil and can tolerate considerable sun if given enough water (keep the soil constantly moist in these conditions), but they do prefer to be planted in areas with full or partial shade. Ensure that soil is well-draining, rich in nutrients, and has a pH of between 4.5 and 7.0 (acidic to neutral). Their ideal substrate is one that is loamy and sandy with plenty of humus. If local soils are particularly poor in nutrients or do not drain well, make sure to amend the planting area with plenty of organic compost before installing. Apply a layer of mulch around the planting area to suppress weed growth, maintain consistent soil temperatures, and to increase soil moisture retention.

Water new plantings regularly as they establish a strong root system in their new home. At maturity, consistent waterings are key to prevent them from drying out, which will cause them to become brown and wilted. Fertilize yearly in early springtime with an application of 2 inches of compost around the base of plants. Pull mulch back before applying, work the compost gently into the soil a bit, water it in, and then replace mulch. Pruning can be done after new growth has appeared; dead and dying areas should be left on the plant until spring because they actually mulch and protect the emerging growth. If these ferns are grown in a cramped space like a narrow border or container, they will need to be divided every few years for best results. For instructions on how to successfully divide your Lady Fern, see the propagation section below.

Propagation

Athyrium ferns are best propagated via division. This type of propagation is relatively simple; you will need a clean shovel, mulch, fresh soil (any kind will do, though it does need to be well-draining), compost, and pots (only necessary if you will be saving divided plants for transporting elsewhere). Division is best done in spring or fall (after the plant has entered dormancy but before it has begun its new spring growth), and needs to be done every few years regardless of whether you have the goal of propagating the plants for best performance. To propagate by division, follow these steps:

Gather your materials. Using a shovel, dig up your existing fern. Start from the outside and work your way in to avoid damaging the roots. Once you have worked it up out of the ground, lay it out.
Start to tease apart the roots with your gloved fingers. Once the roots are untangled, separate your fern into segments, ensuring that each one has at least one thick root section.
Prepare your pot(s) or new planting site(s) with amended, well-draining soil. You can either bring in new soil or simply amend your existing soil with compost to complete this task. Then, plant your divided ferns in soil at the same height as they were previously, and water thoroughly.
Apply a thick layer of mulch around the new planting to protect it from cold weather as it acclimates to its new home. Then, enjoy watching it grow.