How to Grow and Care for Northern Maidenhair Fern (Adiantum Pedatum)

Adiantum pedatum, the Northern maidenhair fern, is a deciduous fern native to the forests of eastern North America and parts of Asia. It's sought after for its striking dark stems and flat, delicate fronds, which are arranged in a circular pattern around a central stem. This shade-loving plant prefers well-drained soil and cool, moist conditions. Adiantum pedatum can be grown indoors as a houseplant or outdoors in the ground or in containers in zones 3-8.

Adiantum Pedatum Care

• Plant in rich, moist, well-drained soil.
• Put in a place with full to part shade.
• Water to keep the soil evenly moist.
• Skip the fertilizer—Northern maidenhair ferns grown outdoors in rich soil don't usually require it.

Light

Plant Adiantum pedatum in a spot with full to part shade. This plant naturally grows on forest floors in shady or dappled light. Plants may be able to tolerate a period of full sun in the morning, but harsh, direct sunlight can burn the leaves.

Soil

Adiantum pedatum should be planted in a spot with moist, well-drained soil that's rich in nutrients. Work organic compost into the soil before planting if the soils are poor. Ensure that the plant won't sit in standing water, which can cause root rot.

Water

Water Adiantum pedatum as needed to ensure that the soil stays evenly moist but not soggy. Water consistently to maintain soil moisture. That may be as often as every day or every other day in very hot, dry weather.

Temperature and Humidity

Adiantum pedatum is adapted to ensure temperatures as low as minus 40 degrees Fahrenheit and prefers cooler temperatures in summer. Indoors, the plant benefits from conditions in the 60 to 70-degree Fahrenheit range and around 50 percent humidity.

Fertilizer

Adiantum pedatum doesn't typically require fertilizer in an outdoor environment. If you feel a need to fertilize, you can top dress with organic compost or apply a balanced slow-release fertilizer in the spring. Choose one or the other, as ferns are sensitive to overfertilizing.

Pruning

Adiantum pedatum does not require regular pruning. Instead, cut back dead or damaged fronds in the fall or late winter to better show off new growth in the spring.

Propagating Adiantum Pedatum

Adiantum pedatum is easy to propagate by division of mature plants in spring before the plants unfurl new fronds. You'll need a shovel, gardening gloves, a clean, sharp knife, and a prepared planting site (or a container and potting mix) where you'll put the new plant. Here's how to propagate Adiantum pedatum by division.

1. Water the mature plant well for a few days before you plan to divide it. If you're planting divisions in the ground, work some organic compost into the soil to prepare the bed.
2. When you're ready to divide the plant, use the shovel to dig beneath the mature plant, then lift up to reveal the crown and root ball.
3. Gently pull apart the root ball into two or three good-sized clumps with your fingers. You can use the knife to cut straight through the root ball if that's easier. Take a moment to remove any dead or dying foliage from the crown of each clump.
4. Plant the divisions in containers or in the ground. Keep the new plants well watered to help them adjust to their new home.

How to Grow Adiantum Pedatum From Seed

Adiantum pedatum reproduces via spores, so it's not possible to grow this plant from seed. You can purchase northern maidenhair fern spores online or gather fronds once the spores have matured.

1. Tap the spores onto a sterilized growing medium in a pot or tray, then mist with distilled water to moisten.
2. Cover the medium with a clear plastic barrier to hold in moisture.
3. Keep the spores at room temperature and provide bright, indirect light.
4. Mist as needed with distilled water. It can take six to 12 months for sporophytes, which can grow into fronds, to appear.

Common Pests & Plant Diseases 

Fortunately, there aren't any significant pests or plant diseases known to affect Adiantum pedatum. If kept indoors, sap-sucking insects like aphids and scale can feed on plants. Like other ferns, the northern maidenhair fern is considered deer resistant.

Common Problems With Adiantum Pedatum

Browning Leaves

Brown, dry leaves can appear when the plant isn't getting enough moisture or receives too much direct sunlight. Fronds may also get brown and dry in very hot summer weather. Water regularly to keep the soil moist, and provide afternoon shade if needed.

Drooping Leaves

Drooping leaves can be a sign of underwatering, a lack of humidity, or even shock from replanting or another sudden change in the plant's conditions. Lack of water and low humidity can be remedied by watering more frequently, especially in very hot, dry weather. Watering well can also help plants recover from transplant shock, but take care not to overwater.

Yellowing Leaves

Leaves turning yellow on Adiantum pedatum are often a sign of overwatering or poorly drained soil, which can cause root rot. Cut back on watering to allow the soil to dry out. In houseplants, the plant may benefit from repotting in a fresh, dry potting mix. If Adiantum pedatum is planted outdoors in an area with standing water or heavy clay soil, you may want to replant it in moist, well-drained soil.