How to grow athyrium

Choosing the right athyrium

There are several species and cultivars to choose from, in various sizes, shapes and colours, so before you buy, consider:

• Height and spread – athyriums range from low-growing Athyrium niponicum 'Silver Falls' at just 30cm (1ft) tall, up to A. filix-femina at 1.8m (6ft) or more. Compact types are ideal for containers and small spaces, while taller types need plenty of space so they can unfurl fully and be displayed to their full potential.
• Leaves – most athyriums are deciduous, so their leaves (or fronds) die down in autumn and re-sprout in spring, unfurling attractively. Athyrium otophorum is semi-evergreen, so in warm, sheltered locations it may keep its leaves all winter. Some cultivars have tinted leaves, often blue-grey or silvery, such as A. niponicum var. pictum
• Soil type – most athyriums like moist but not
  Describes soil or potting compost that is saturated with water. The water displaces air from the spaces between soil particles and plant roots can literally drown, unless they are adapted to growing in waterlogged conditions. Waterlogging is common on poorly drained soil or when heavy soil is compacted. 

  waterlogged soil, although A. filix-femina tolerates damper and more acidic soil, while others prefer slightly moist, neutral soil. See our guide to assessing your growing conditions.

How and what to buy

Athyriums are widely available in garden centres and nurseries, often in 3 litre pots. For specific cultivars, try specialist nurseries including Long Acre Plants and Crawford Ferns. For more suppliers, go to RHS Plant Finder.

Where to plant

Athyriums like moisture-retentive but not waterlogged soil. Most originate from woodlands, so need shade or semi-shade. A few, such as Athyrium filix-femina, are more tolerant of brighter locations, but the leaves may become scorched and they need the soil to remain moist throughout summer to do well. 

They are best grown in a sheltered location, away from strong winds and frost pockets. Other ferns such as Dryopteris and Polystichum may be more tolerant of exposed positions.

These ferns can be used in a wide range of garden styles, but particularly suit a woodland-style setting. Try planting them around old tree stumps and logs, and use a mulch of composted bark, for a naturalistic feel. You could even create a stumpery. Ferns also suit a Japanese-themed garden.

When to plant

• It is best to plant in autumn or spring when the soil is naturally moist
• If you buy in summer, plant as soon as possible and water regularly to keep the soil moist

How to plant

These ferns are easy to plant, in a similar way to most perennials – see our guide below. They just have a few specific requirements:

• Ensure there is plenty of space for the fronds to unfurl fully. Check the label for the plant's width/spread and allow this gap between plants
• Once firmed in, the plant should sit at the same level it was in the container. Avoid planting more deeply, as that may cause the base of the plant to rot
• Water in well, then cover the surrounding soil with a thick mulch of composted bark or leaf mould, to hold in moisture. Again, avoid covering the crown of the plant, as this could lead to rotting

Planting Perennials

Planting Perennials

• Newly planted athyriums should be watered as needed, especially during summer, for the first few years, until their roots are well established
• Athyriums like damp conditions, so in prolonged hot, dry spells or in free-draining soil, plants may need additional watering
• Plants in containers also require watering throughout the growing season, as the small amount of compost dries out rapidly
• Direct the water to the roots and not onto the fronds or crown, as this can encourage rot

Water: collecting, storing and re-using

Water: collecting, storing and re-using

• Athyriums don't usually require feeding, but adding a mulch annually, such as well-rotted farmyard manure or garden compost, will improve the soil and boost growth

How to feed plants

How to feed plants

By division

The easiest way to propagate athyriums is by dividing the clump, in a similar way to most other perennial plants. There are two main methods:

• If the fern has formed several crowns, these can simply be prised apart, then replanted individually
• With ferns that have creeping underground stems (rhizomes), these rhizomes can be cut into short sections, each with a growth bud and roots, and replanted

For step-by-step instructions on both methods, see the propagation section of our guide to growing hardy ferns.

RHS guide to dividing perennials

RHS guide to dividing perennials

Growing from spores

Growing new ferns from spores (the ferns' equivalent of seeds) is a more tricky and slower process. But it's a fun and interesting challenge for more experienced gardeners. For step-by-step instructions, see the propagation section of our guide to growing hardy ferns.