Chrysosplenium macrophyllum

Some plants are so unusual, so distinctive, that you never forget your first encounter with them. This was the case for me with Chrysosplenium macrophyllum, a plant I saw for the first time at the famous Crûg Farm Nursery in North Wales. It might have been my visit in 2009, and the sun was shining… in a ‘long tom’ pot by the entrance to the nursery was a single rosette of a Bergenia-like plant with long wine-red runners hanging down over the edge of the pot. I’d never seen anything quite like it, and of course it wasn’t available for sale at that moment.

Chrysosplenium macrophyllum is both familiar and strangely unfamiliar in equal measure; initially the rosettes of leaves and the general look of the plant bring to mind the ever-familiar genus Bergenia, and indeed both are found together in the Saxifragaceae (but then so is Rodgersia!). However the leaves aren’t as tough and waxy as those of most Bergenias, and are more actually more akin to Hylotelephium leaves in their succulence. The hairs on the leaves are strangely fleshy and could well be regarded as ‘unpleasant’ by some. Winter cold tends to give the foliage a sort of reddish-pink flush.

Chrysosplenium macrophyllum on a woodland floor

The flowers are produced in charming open heads in January or February, depending how mild the winter is. What looks like a whitish-grey inflorescence is, on closer inspection, a sort of metallic silver. The strange ‘metallic paint’ effect is caused by a layer of transparent cells on the upper surface of the floral bracts. As you look closer you also see the sets of tiny candy-pink stamens of each flower.

Chrysosplenium macrophyllum. Note the metallic sheen to the bracts

After flowering, as winter yields to spring, a set of wine-red runners emerges from the centre of each mature rosette. These retain their colour as they reach out across the ground. New rosettes are formed at the end of each runner, producing foliage before roots; if you intend to propagate this species it’s advisable to wait until the new plants are well rooted and the runners are dying away before you try to dig up the young plantlets.

C. macrophyllum is proving reliably hardy in the UK, although the coldest weather can make the largest leaves look a little sad by the end of the winter. This is possibly a matter of opinion; where some people see ‘stressed foliage’ others see ‘winter colour’.

It’s believed that Chrysosplenium macrophyllum was first introduced to the UK from China by Chen Yi Nursery in the early 2000s, and thanks to its fairly easy propagation it was quickly shared around the specialist nurseries and rare plant enthusiasts. What’s quite surprising is that it was first published in Joseph Hooker’s ‘Icones Plantarum’ in 1888, yet it took over a century to actually introduce this plant into cultivation. Maybe it wasn’t deemed ornamental enough by previous generations of explorers, but you have to wonder what people like Graham Stuart Thomas would have thought of this plant had it been introduced earlier? Modern gardeners certainly seem keen on this species, and it usually gains a favourable response when encountered at plant fairs.

While Bergenia is an established genus with several species that have been crossed to form a range of hybrids, Chrysosplenium macrophyllum is unlikely to ever yield many clones or cultivars. The rest of the genus is made up of creeping, mat-forming plants with fleshy leaves and, nearly always, lime green or acid yellow flowers, and the hopes of interbreeding between the different species are probably pretty low. In fact Chrysosplenium macrophyllum is so different from the rest of the genus that I wouldn’t be surprised if it was discovered to represent its own genus. Sure it has similarities with the rest of the genus, but the differences are quite notable. Whether C. macrophyllum gets its own genus or remains as an oddball member of the genus Chrysosplenium is an argument for taxonomists.

“Until I noticed its stoloniferous habit, I was ready to proudly proclaim to my travelling companions that I had found a Bergenia. In fact, this similarity is what ultimately led me to its proper identity, as Roy Lancaster had had precisely the same reaction when he found C. macrophyllum on Wudang Shan in the same province in 1983.”

Daniel J. Hinkley, The Explorer’s Garden

Chrysosplenium macrophyllum is native to temperate parts of Central and Southern China. While it failed to catch the attention of earlier plant hunters in that part of the world, in more recent years it has been noted by Roy Lancaster at Emei Shan in 2008 and by Martin Rix near Foping in Shaanxi Province in 2010. It’s interesting, given the success of this species, there haven’t been more attempts to introduce variations of this species from the wild; it’s unlikely that a plant spread out over such a vast area and over varying terrain doesn’t have different leaf forms, but the only different clone of the species in cultivation that I’m aware of is a clone grown at the Potsdam Botanical Garden in Germany. The ‘Potsdam clone’ differs from the ‘Chen Yi clone’ in having narrower leaves, redder new growth and winter colouring, and being slower growing. Florally both clones are very similar.

In cultivation this is most definitely a shade-loving species, but while Chrysospleniums generally prefer damp to wet conditions, C. macrophyllum can tolerate drier soils in shadier conditions (so the more sun it gets the more moisture it needs). It should be noted that spread will be curtailed in drier soils and that the plant is usually more compact in habit. At RHS Rosemoor there is, or at least was, a patch of this species in full sun and ‘ordinary’ soil, making a dense mat that never looks/looked happy, and usually very pale and scorched-looking.

The spread of C. macrophyllum could be offputting to some gardeners; what’s billed as a ‘rare new treasure’ in nurseries and at plant fairs is not shy about growing when it’s happy, and often gardeners are put off by the idea that a plant can produce runners over 30cm (1ft) long in every direction every year. This plant does not become a nuisance; a single rosette will produce up to ten runners if you’re lucky, usually anything between three and seven, and these will spread across the ground and deposit the same number of individual rosettes. The runners are a little brittle so mechanical injury can be an issue, as can dry weather in spring. Each runner can easily be guided to where you want it if desired, but generally the plant is happiest colonising an area in its own time. If you really don’t want it to spread further simply snap off the runners and the plant won’t make any more during that year. Rooted plantlets are easily dug up and replanted. For those who really, really can’t be bothered to curb the spread of this plant the slower growing ‘Potsdam clone’ would be the better choice when it becomes available.

Chrysosplenium macrophyllum is a charming and distinctive plant that has a promising future in gardens. Its bold and unusual appearance and early flowering season are sure to make it a firm favourite as it becomes more widely known.