Arachniodes

( ar - ak - nee - OY - dees )

At-A-Glance Information

This genus of ferns needs partial to full shade and regular to ample water. Native to Japan and China, this plant is evergreen where winters are mild/warm, and deciduous in frostier regions. Leaves are finely divided and deeply cut. Species in the genus are commonly called Shield Ferns, Holly Ferns, Bristle Ferns, or Spider Ferns and are fantastic understory plants that add tufts of foliage to woodland and shade gardens. Take care when planting these ferns in the garden, as some species are known to be toxic to humans and pets if ingested.

arachniodes Species and Varietals

The genus Arachniodes is a member of the plant family Dryopteridaceae and includes 78 species. The genus name is derived from the Greek word arachne, meaning spider, referring to the spidery aspect of the spore clusters found on the undersides of fronds. These ferns grow best in USDA hardiness zones 7-10 or Sunset growing zones 4-24. To find your zone, click here: Zone Map.

Arachniodes aristata (Prickly Shield Fern, East Indian Holly Fern, Bristle Fern, Bearded East Indian Holly Fern, Aristate Holly Fern)
This species produces glossy green foliage and fronds that stretch up to 3.3 feet long. Individual plants typically reach a height of between 1.5 and 3 feet tall at maturity. Cultivars include 'Variegata' (with lighter midribs), 'Blackie', 'Bronze Pink', 'Margarita', 'Tricolor', and 'Okoze' (a compact variety).

Arachniodes simplicior (Simpler East Indian Hollyfern, Variegated Shield Fern, Simpler Holly Fern, Shield Fern)
This species is native to China, and includes a variety of garden ornamental cultivars available for purchase at most nurseries, including 'Variegata' (with lighter frond centers, pictured). Individual ferns typically reach up to 1-2 feet tall and 1.5 to 3 feet wide when mature.

Caring for arachniodes

Plant Arachniodes in a space in the garden that receives partial to full shade. A spot that gets morning sun and afternoon shade is a good compromise if full shade is hard to come by in the landscape. Ensure that soil is well-draining, rich in organic material and nutrients, and has a pH of between 5.0 and 7.0 (slightly acidic to neutral). 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 themselves in their new home. At maturity, Shield Ferns appreciate consistently moist soils. As a general rule of thumb, water whenever the top inch or two of soil feels dry to the touch.

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. These plants are not heavy feeders, and this should be sufficient to provide the necessary nutrients for the active growing season. Pruning is simple; remove any damaged, diseased, or dead fronds at any time during the growing season. Every few years, especially if these ferns are grown in a cramped border or container, they will need to be divided to ensure ongoing health. Division also can improve airflow, lessening fungal issues like powdery mildew. For instructions on how to successfully divide Arachniodes, see the Propagation section below.

Propagation

Arachniodes ferns are best propagated through division of existing plants. Spores can be used to propagate as well, though doing so requires more specialized knowledge, previous experience, and a suitable medium. To learn more about propagating ferns through the use of spores, see the Propagation module. To propagate your Arachniodes fern by division, follow the directions below:

Propagating Arachniodes by 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 very early spring (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:

Using a shovel, dig up your existing plant. 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 fingers. Once the roots are untangled, separate your plant into segments, ensuring that each one has at least one thick root section attached.
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 divisions and water thoroughly.
Apply a thick layer of mulch over the new planting to protect it from cold weather as it acclimates to its new home. Then, enjoy watching it sprout in the next growing season.

Problems and Pests

Arachniodes, or Shield Ferns, are generally resistant to issues in the landscape, but can from time to time suffer from problems with the following pests and diseases: