<em>Rodgersia</em>: planting, cultivation, care

Description and botany

The Rodgersia is a perennial in family Saxifragaceae, native to humid, mountainous areas, cool forests and copse of Myanmar, Korea, China and Japan. This plant has acclimatised to our temperate gardens and parks.

Genus comprises 6 species and numerous cultivars. Among those most common in our climates are Rodgersia aesculifolia, often called “horse-chestnut-leaved Rodgersia”, Rodgersia pinnata or “pinnate-leaved Rodgersia”, Rodgersia podophylla or “duck’s-foot-leaved Rodgersia”, Rodgersia sambucifolia or “elder-leaved Rodgersia” and Rodgersia aesculifolia var. henrici, a natural variety of horse-chestnut-leaved Rodgersia.

Rodgersia takes 3 to 5 years to establish well and reach full development. The plant develops slowly from fleshy, scaly, running rootstock. It will remain vegetative in the first years, flowering only after two years in cultivation. Its slowness to establish is matched by its great longevity! Not invasive, it gradually spreads to form stumps over 1 m² and slowly colonise ground over time.

It is a plant with an architectural, bushy habit. Rodgersia forms a fairly dense, imposing clump that can reach 1.50 m in height in flower, with a spread of 2 m.

Rodgersia is notable for its vigorous, majestic growth. This deciduous foliage, particularly elegant and graphic, disappears completely in autumn at the first frosts.

In spring, the fleshy stump produces a generous tuft of large petiolate leaves, pinnate or more or less palmate with more or less dentate margins. Leaves can reach 80 cm in length, divided into 3 to 11 large leaflets, lanceolate, oblong or obovate.

Some foliage: Rodgersia pinnata, Rodgersia ‘Bronze Peacock’, Rodgersia podophylla (photo Megan Hansen-Flickr), Rodgersia pinnata ‘Dark Pokers’

Some leaves are wooly or rough, others glossy; most are crumpled or puckered, deeply veined. Foliage of Rodgersia pinnata strongly resembles that of horse chestnuts, while foliage of Rodgersia podophylla is as palmate as a “duck’s foot”!

Green, veined with reddish-brown in Rodgersia aesculifolia, and bronze then dark green turning purple, red or orange in autumn in Rodgersia podophylla, tones of this ample palmate foliage vary by species and cultivar, sometimes changing through the seasons.

Foliage development of a Rodgersia podophylla: young leaves dark purple in spring, green in summer and orange-red in autumn

What distinguishes form henrici from the type species Rodgersia aesculifolia is its young spring foliage bronze-purple at bud burst period, becoming dark green in summer.

Some cultivars of Rodgersia pinnata such as ‘Bronze Peacock’ and ‘Chocolate Wings’ develop changing foliage, evolving from bronze-brown or chocolate-brown to deep red before fading.

Summer flowering in large, cloud-like panicles on tall, sturdy stems of Rodgersia often takes spectacular forms.

From early to late summer, the plant sends up large, impressive spikes of flowers, sometimes carried up to 1.5 m well above the palmate foliage. These large, plume-like branched inflorescences 20 to 70 cm long bear clusters of star-shaped flowers in pure white, ivory or pale to purplish pink, borne on sometimes reddish stems. They give way to capsules in dark red or brown, of little decorative interest.

Some Rodgersia flowers: Rodgersia pinnata ‘Superba’ (photo Rob Bakker-Flickr), Rodgersia pinnata ‘Chocolate Wings’, Rodgersia aesculifolia ‘Irish Bronze’, ‘‘Rodgersia ‘Bronze Peacock’

The very graphic, airy, plume-like spikes make beautiful fresh summer bouquets.

Despite its exotic appearance, Rodgersia shows good hardiness down to at least -25°C. It is a shade- and cool-loving plant, ideal near water features or at edges of damp woodland understory, where it brings an exotic lushness.

It prefers cool, moist, water-retentive soils, with a preference for non-calcareous ground; a typical acid or neutral woodland soil will suit it perfectly! It is an indispensable perennial for heavy soil. It will tolerate non-scorching sun only if soil remains well moist at depth during summer.

Main species and varieties

Most popular

Our favourites

Rodgersia aesculifolia

Leaves resembling horse-chestnut form a handsome bushy clump with starry cream-white flowers, turning pink towards end of flowering.

• Flowering time September, October
• Height at maturity 1 m

See the product sheet

Rodgersia podophylla

Forms a majestic clump of large palmate leaves bronze when they first appear, later dark green with bronze highlights, becoming purple, red or orange in autumn.

• Flowering time July, August
• Height at maturity 1 m

See the product sheet

Rodgersia pinnata

Foliage of this variety closely resembles that of horse-chestnut. Ideal by water features, in company with ferns and grasses.

• Flowering time July to September
• Height at maturity 1 m

See the product sheet

Rodgersia aesculifolia var. henrici

One of the most spectacular, with flowering in large, cloud-like pink-purple panicles over striking dark-green horse-chestnut foliage. A true star of cool, damp places!

• Flowering time August, September
• Height at maturity 1,20 m

See the product sheet

Rodgersia pinnata Bronze Peacock

Palmate horse-chestnut foliage in antique bronze-brown, almost metallic, changing through seasons. Irreplaceable in moist, shady spots, even when space is limited.

• Flowering time July, August
• Height at maturity 50 cm

See the product sheet

Rodgersia pinnata Chocolate Wings

A striking Rodgersia with an architectural habit and broad palmate horse-chestnut foliage of chocolate brown that changes through the seasons.

• Flowering time August, September
• Height at maturity 1 m

See the product sheet

Rodgersia aesculifolia Irish Bronze

Loved for its large decorative bronze leaves and pink flower buds that open to ivory white.

• Flowering time June, July
• Height at maturity 1 m

See the product sheet

Planting

Where to plant Rodgersia

Hardy, Rodgersia withstands frosts down to -25 °C; it thrives in cool, humid regions and particularly on the north‑west coast. Cultivation can be more difficult in Mediterranean climates that are too dry and hot in summer.

Its only requirement is moist soil; this plant does not tolerate lack of water: it will wither in dry soil. Rodgersia dislikes drought.

It prefers shade and coolness but will tolerate sun in temperate regions, provided the soil remains always moist and cool. Place it sheltered from dry, cold winds and direct sun that could damage its foliage.

Easy to grow, it will be most luxuriant in soil rich in organic matter and will develop vigorously.

It typically prefers understorey soil, neutral or acidic, free of lime.

Although it likes rather heavy soils that never completely dry out in summer, it does fear excess water during winter; give it perfectly drained soil.

Choose a well‑exposed position to encourage it to reach full size. It is a very impressive perennial that slowly but surely forms fairly opulent clumps up to 2 m in spread without ever becoming invasive despite its running rootstocks. Foliage becomes truly ample when the plant is grown in a semi‑shaded spot with high ambient humidity in summer.

Rodgersia comes into its own as a understorey plant, waterside plant, on pond banks, lighting them up with its bright flowering and imposing palmate foliage.
It will make an impact in beds of fresh heather soil, as a solitary specimen or planted in numbers along a shaded path.

When to plant Rodgersias

Rodgersias are best planted in autumn (September–October) in temperate zones, or in spring from March to May in cold climates.

How to plant Rodgersia

In open ground

Space plantings well: when mature, Rodgersia reaches a spread of 1 to 2 metres. Do not be deceived by its small size in the bucket!

Ensure plants are at least 0.70 to 0.80 m apart in worked, loosened soil enriched with well‑rotted compost or manure.

• Dig a hole 2 to 3 times wider than the root ball
• Fork over the soil to 30–40 cm depth
• Spread a layer of gravel at the bottom of the planting hole
• Add a good shovelful of well‑rotted compost or manure to the bottom of the hole before placing the root ball
• Backfill to enclose the roots and firm down
• Water copiously until establishment and throughout the first year after planting
• Mulch the base carefully in late May with an organic mulch to preserve moisture during summer

Planting Rodgersia in a pot

Despite the vigorous growth of this perennial, pot culture is possible because Rodgersia’s roots are fairly shallow. However, the rootstocks can quickly escape their container: provide a large pot of at least 70 cm diameter.

• Plant the root ball in a mix of garden soil, clay‑based and enriched
• Spread a good layer of gravel or expanded clay pebbles at the bottom of the pot beforehand to improve drainage
• Mulch
• Water very regularly; never allow the substrate to dry out

Care and maintenance

This plant is not delicate and will easily be forgotten provided conditions suit it.

Rodgersia is a perennial that likes water. It forms large, exotic-style displays until frosts, but it needs frequent, generous watering!

Coolness and moisture at its base are the secrets to grow this colossal perennial! Soil must be kept sufficiently moist, otherwise it will quickly perish in prolonged drought. A cool soil will allow vigorous development.

Water very regularly during first year to ensure good establishment. Afterwards, only once a week, especially during hot spells.

Mulch in late May to reduce watering and evaporation. In very cold climates, mulch the stump with dead leaves in autumn; late frosts may damage young, tender shoots.

Every two years, in March, spread a few shovelfuls of compost over the stump.

Remove faded flower stems after flowering to favour foliage development or leave them standing to dry for seed harvest.

Wait until spring to tidy the clump and remove withered leaves.

Divide the stumps into pieces in March to ensure plant longevity.

Diseases and potential pests

Hardy and robust, Rodgersia has few enemies.

It is, however, sensitive to dry, cold winds, scorching sun and to slugs in spring, which can damage young shoots, though much less than with hosta, its shade companion. Use mechanical traps or apply a slug treatment every year from February. Try our natural methods!

Rodgersias grown in pots can be more vulnerable, notably to vine weevil larvae that devour the roots… Watch for attacks by these small beetles that ‘punch’ the leaf edges: burn them, remove young plants that are too heavily infested. Spray with tansy decoctions.

Propagation

Sowing Rodgersia is possible, but requires a lot of patience. We recommend instead dividing stumps in spring in March. Only intervene after 4 or 5 years when plant is well established.

1. Using a garden fork and spade, lift part of stump before foliage develops
2. With a spade, cut a healthy clump
3. Replant offsets immediately into well-worked soil enriched with compost

Associate

A must in shaded gardens and by water in marsh gardens, Rodgersia with its imposing foliage of large palmate leaves and its pastel plume-like inflorescences brightens cool spots.
At the edge of a cool, damp understory, it is perfect with shade companions such as ferns, Ligularia, Peltoboykinia, Cierge d’argent, Epimedium, Filipendula, Heuchera or alongside Asian primulas or Begonia grandis evansiana.

An example of a pairing: Hostas, Rodgersia podophylla, Catalpa bignonioides ‘Aurea’, flowering dogwoods (Le Sous-Bois, Belgium)

Classic Rodgersia partners, astilbes and hostas enjoy the same growing conditions and make an impact in a cool, shaded border.

Among its top partners are grasses (Carex, gardeners’ rush, Japanese rush, tufted hair-grass).

At the pond edge, pair it with other perennials for damp margins such as Gunnera or Darmera, marsh euphorbias, Siberian irises, perennial lobelias.

An idea for a pairing at a pond edge: Gunnera tinctoria, Rodgersia pinnata ‘Hercule’ (R. pinnata or other species are equally suitable), Iris sibirica (‘Blue King’, ‘Caesar’s Brother’), ferns…

Rodgersia complements a bed of bushes on heather soil such as rhododendrons.
To enhance the edge of a shaded path, set it off with a tapetum of groundcover polygonums, golden Sagina, candelabra primulas and hepatics.

Its handsome palmate leaves, often turning a reddish bronze in autumn, harmonise well with a wide range of trees and bushes with late colouring such as maples, barberries and deciduous euonymus, smoke trees, sumachs and grasses with autumn tones.