What hardiness zones is Adiantum suitable for?

Adiantum is suitable for USDA hardiness zones 3, 4, 5, 6, 7, 8.

Ferns

Adiantum

Maidenhair Fern

Pteridaceae

Adiantum pedatum native to North America; Adiantum venustum native to Himalayas; many tropical species worldwide

At a Glance

TypeFern

HabitMounding

FoliageDeciduous

Height12–24 inches (30–60 cm)

Width12–24 inches (30–60 cm)

Maturity3 years

Growing Zones

USDA Hardiness Zones

3 - 8

Zone 3

Zone 4

Zone 5

Zone 6

Zone 7

Zone 8

These zones indicate the coldest temperatures this plant can typically survive.

Frost Tolerancehardy

Key Features

Deer Resistant

Container Friendly

Native to North America

Maintenancemoderate

Overview

A genus of approximately 200 species of deciduous and semi-evergreen ferns grown for their delicate, lacy fronds with distinctive black to dark purple-brown wiry stems that contrast sharply with bright to mid-green fan-shaped or wedge-shaped leaflets. Most garden-grown maidenhair ferns reach 12–24 inches (30–60 cm) tall and 12–24 inches (30–60 cm) wide, forming slowly spreading clumps. The two species most commonly cultivated in Pacific Northwest gardens are Adiantum pedatum (northern maidenhair fern), a North American native with a distinctive hand-like frond arrangement, and Adiantum venustum (Himalayan maidenhair fern), which is semi-evergreen and somewhat more drought tolerant. All prefer shade and consistent moisture. Fronds are sensitive to drying winds and drought — they collapse quickly but often recover with watering.

Native Range

Adiantum pedatum is native to moist woodland and forest floors across North America, from Alaska and British Columbia south through the Pacific Northwest, east to the Atlantic coast. Adiantum venustum is native to the Himalayas. Many other species are native to tropical and subtropical regions worldwide.

Suggested Uses

Used in shade gardens, woodland plantings, and stream-side settings at 18–24 inch (45–60 cm) spacing. The lacy texture and black stems provide exceptional contrast with broad-leaved shade plants such as hostas, Astilbe, and Trillium. Adiantum pedatum is an excellent native plant choice for Pacific Northwest shade gardens. Suitable for containers of 2+ gallons (7.5+ L) kept consistently moist.

How to Identify

Identified by the combination of wiry black to dark purple-brown stipes and rachises, fan-shaped to wedge-shaped bright green pinnules, and delicate lacy frond texture unlike any other common garden fern. Adiantum pedatum distinguished by its distinctive horseshoe-shaped frond arrangement, with pinnae radiating from a forked rachis like fingers on a hand. Adiantum venustum distinguished by its more triangular, finely divided fronds that are semi-evergreen and emerge bronze-pink in spring.

Appearance

Size & Dimensions

Height1' - 2'

Width/Spread1' - 2'

Reaches mature size in approximately 3 years

Colors

Foliage Colors

green

Fall Foliage Colors

no change

Bloom Information

Ferns do not flower. Spores form on the undersides of pinnule margins, which fold under to create false indusia. Spores ripen in late summer. Not grown for reproductive structures.

Detailed Descriptions

Foliage Description

Bright to mid-green fan-shaped or wedge-shaped pinnules on contrasting wiry black to dark purple-brown stems

Growing Conditions

Sun Requirements

Partial Shade

Full Shade

Tolerates up to 4 hours of direct sunlight daily

• Full Sun: 6+ hours of direct sunlight

• Partial Shade: 3-6 hours of direct sunlight

• Full Shade: Less than 3 hours of direct sunlight

Soil Requirements

pH Range5.5 - 7.0(Neutral)

357912

Soil Types

loampeat

Drainage

moist

Water & Climate

Water Needs

High

Frost Tolerance

hardy

Time to Maturity

2–3 years

Care & Maintenance

Care Guide

Plant in part to full shade in consistently moist, humus-rich, well-drained soil. Space clumps 18–24 inches (45–60 cm) apart. Keep soil evenly moist — maidenhair ferns are among the least drought-tolerant ferns and fronds collapse rapidly when dry. Mulch generously with leaf mold or compost to retain moisture. Protect from drying winds. Remove old fronds in early spring before new growth emerges. Divide in early spring every 3–5 years to maintain vigor.

Pruning

Cut back all fronds to the ground in late winter to early spring before new growth begins. Remove individual fronds that collapse due to drought or wind damage. Adiantum venustum fronds may be left through winter in mild climates as they remain semi-evergreen.

Pruning Schedule

early spring

Maintenance Level

moderate

Container Growing

✓ Suitable for container growing

Minimum container size: 2 gallons

⚠️ Toxicity Warning

Non-toxic