Rodgersia – An Eastern Asia Genus
In the 1850s United States Admiral John Rodgers, in command of the North Pacific Exploring and Surveying Expedition, spent some five years sailing the seas around China and Japan. They had scientists charting the seas and also biologists and botanists on board and although much was discovered, very little was published. Many plants were brought back but it was not until 1888 that taxonomist Professor A Gray described Rodgersia podophyllum, naming it after the Admiral of the expedition.
Since then plant hunters on further expeditions have sourced more Rodgersia but they all seem to be native to East Asia, especially Nepal, Korea, China and Japan. They are easily identified with their large architectural leaves and tall spires of flowers. They have been described as large Astilbe and beautiful rhubarb, so I’m sure you get the picture. They are Saxifragaceae. Adrian Franchet, the French botanist, described Rodgersia pinnata as Astilbe pinnata. The Irish plantsman Augustine Henry acquired seeds in 1898 and sent them back to Kew where it was grown and flowered in 1902. He had collected these seeds in Yunnan at 2000m above sea level. At first the plants were not considered to be hardy and graced the conservatories of the Victorians where they created a jungle effect. However it was not long before they were recognised as hardy – hardy that is as a hardy perennial, although the late spring frosts can do a lot of damage to the emerging new growth.
Rodgersia have a lot to commend them. They are architectural plants for the garden. They are large both in height and spread reaching one to two metres tall and across.
Their leaves are pinnate or palmate and deeply veined giving them a coarse texture. Spring and autumn colour are good. Most plants have bronze spring foliage and this colour can either remain all summer or change to green then back to bronze, pinkish red or as in R. aesculifolia, yellow in the autumn before the first frost takes them down completely.
The flowers are petalous in a pyramid shaped panicle in a variety of colours-white, cream, pink and red, mostly appearing in early summer. The dead flower spikes can be cut down but the seed capsules are starlike and turn red in the Autumn so extending interest in the garden.
In the wild they grow along streams and pond margins in rich moist organic soils. They like the soil to be moist but well drained. They seem to grow where there is shelter from harsh winds and direct sun which dry out the leaves.
There are five species in the genus, R. podophylla, R. pinnata, R. aesculifolia, R. sambucifolia and R. heinricii, but there are increasingly more cultivars within each species. One hundred and fifty years old and suddenly this plant is rapidly gaining in popularity. R pinnata and R. podophylla are the most easily found. R. sambucifolia the rarest, although becoming more widely available in the trade. Similar to Rodgersia and at one time classed as one is Astilboides tabularis which has softer light green foliage and is an excellent plant to grow alongside as a contrast.
Among the cultivars of R. podophyllum are the semi dwarf R. p. ‘Smaragd’ with bright green leaves and R. p. ‘Rotlaub’ which recently was awarded the RHS AM for its creamy flowers and dark red foliage. There are many R. pinnata cultivars all with varying degrees of bronze foliage. R. p. ‘Die Schöne’, a German selection, has deep pink flowers, R. p. ‘Fireworks’ has cherry red flowers and really bronze spring foliage, R. p. ‘Chocolate Wing’ has dark purple bronze foliage with deep pink flowers, R. p. ‘Elegans’ has pale pink flowers and the odd one out R. p. ‘Alba’ has white flowers and bright green foliage.
Apart from the problem with late spring frosts and maybe slugs they are easy to grow. The root is a thick rhizome which makes it easy to divide in Spring when the new buds can be seen. The species can also be grown from seed and takes two or three years to come to flowering.
If you have a sheltered spot in the garden that can be guaranteed moist for most of the year, back of the border if there is no hedge to compete for water, give this stunning plant a try. We decided to do just that and bought one, then another, then another and my favourite one – well I cannot say other than “the one I’m looking at” as they are all really interesting both close up and at a distance, on their own or as part of a mixed bed.