Helleborus foetidus at Midmar Paddock, Edinburgh, growing against the boundary wall in late January 2023. Note the palmate leaves, the lower ones significantly serrated. On the other side of the wall is a field of allotments, suggesting that this plant could have originated from a cultivated specimen. Perhaps seeds were carried through the wall by ants (see text for full explanation). Photo: John Grace.
Anyone living in the south of Edinburgh knows Midmar Paddock, a grassy field at the foot of Blackford Hill, beloved by dog walkers and joggers. The present owners would love to build on it, even though it is designated as part of Edinburgh’s Green Belt and a Local Nature Reserve. In 2015 we visited the site to assess its diversity: we recorded 75 plant species and passed our list to those who were opposing the development. This week we feature a species we didn’t see, the Stinking Hellebore. Apparently it is a rather recent arrival. I first saw it three years ago, and it is still there.
Detail of the plant shown above, illustrating the drooping inflorescence, the globose flower and the tendency for purple pigmentation. The ‘petals’ are modified sepals and the nectaries (see the cut-away flower below) have evolved from the true petals. Photo: John Grace.
The Stinking Hellebore (Helleborus foetidus) is a member of the buttercup Family Ranunculaceae. It looks quite other-worldly with its yellow-green flowers and its purple tinge, but I was surprised to discover that it is a native species, featured with several of its relatives in Gerard’s Herbal in 1597. I was even more surprised to read that it’s on the UK list of ‘Scarce Species’ (Stewart et al 1994). However, there is confusion between the truly ‘wild’ species and the many cultivated forms which have ‘escaped’ and are sometimes found in the wild.
In its ‘wild’ native form it is found in the south of England, growing on chalky soils, often in a woodland setting or in hedgerows. There are scattered records of Helleborus foetidus in Scotland but it is impossible to tell whether the recorder has distinguished between the wild type and the cultivated forms. The first record in Scotland is in Thomas Hopkirk’s Flora Glottiana from 1813: “Banks of the Clyde at Blantyre Priory, abundantly. Old walls, Barncluith”. Perhaps it was cultivated by the monks. It is now quite a rare species in Scotland. For example in Midlothian there are only six records, dating from 1927 (at Corstorphine) to 2021 (Dalhousie Business Park). Elsewhere, Brian Ballinger’s Checklist of the Urban Flora of Scotland says it is “a scarce garden escape”, and Peter Macpherson reports a few historic sightings in The Flora of Lanarkshire.
A garden form of Helleborus, at a public park at Saughton, Edinburgh. The flowers are more open, the ternate (not palmate) leaves have more prominent marginal teeth, and winter damage is evident. It may be H. argutifolius (Corsican Hellebore), one of several species that have the RHS Award of Garden Merit. Photo: John Grace.
When I have seen Stinking Hellebore in gardens it has been more ‘showy’, with larger flowers and with leaf margins that are more serrated than the one I found at Midmar Paddock. Also the cultivated forms have flowers that open more widely and do not droop as much. The garden forms may have been imported from southern parts of Europe, and some of them may be hybrids. There are at least a dozen garden varieties (see Rice 2002). Naturally, I was curious to see whether the Midmar version was the wild or cultivated type, and so I wanted to take a look at the original specimens that Carl Linneaus used in 1735 when he named and described the plant. In former times this would entail travelling to the Linnean Society in Piccadilly, London where most of Linneaus’s collection is housed as dried specimens. But now they are online here, and I was pleased to see that his two herbarium sheets are a good match to the Midmar specimen. The plants I found in the flower bed of the Royal Caledonian Horticultural Society at Saughton in Edinburgh are clearly cultivated forms, and they seem to have suffered more from this harsh winter.
Stinking Hellebore doesn’t stink as much as its name suggests. People have said the smell of crushed leaves is like roast beef, wet dog or coffee. One of its alternative names, Dungwort, seems especially unfair. A third name, Bear’s-foot, presumably suggests a resemblance to the shaggy foot of the noble beast that roamed Britain over 1000 years ago. It is poisonous, especially the roots. Vickery’s book, Plant Lore, recalls the death in 1762 of two children within a few hours of eating it. In moderate doses, it has been used as medicine, as Rice (2002) tells us.
A specimen from a private garden, Inveresk, East Lothian. Note that this one has more pigmentation of the flower but is otherwise similar to the Midmar plant. We believe both are the ‘wild type’. Photos: Chris Jeffree.
It’s an evergreen perennial that lives for 3-5 years, and starts flowering in January. There are few insects around at this time of year, but it does manage to attract them despite the fact that the flowers point downwards. It has a very special mechanism of attracting insects. The large nectaries become colonised by yeasts, which ferment the sugary nectar and warm the flower, also releasing volatiles from the brew. Bumble-bees are attracted by the smell. Don’t believe it? Neither did I until I looked at this paper.
Here the flower has been cut away to show the many stamens and the several nectaries. The nectaries are the trumpet-shaped structures surrounding the stamens, visited by Bumblebees. Photo: Chris Jeffree.
The seeds have ant-attracting, food-rich bodies (elaiosomes) on their surfaces, and so the worker-ants fetch the seeds and carry them to their nests for food. This is the main (possibly only) means of dispersal. The mechanism is called myrmecochory and has evolved independently in many plant families. The process may extend further in this species. Researchers in Spain have shown that when the ant removes the elaiosome (by eating it) the seed is more likely to germinate.
Helleborus foetidus, comparing its British distribution pre-2000 (left) and after 2000 (right). It is apparently spreading. However its spread may reflect garden escapes. Also, recent recording may have been more thorough. It may be declining in its natural range as some people have suggested, because of the removal of hedgerows. Data and graphics: BSBI.
According to Plants of the World Online, Helleborus foetidus is native to Baleares, Belgium, Corsica, France, Germany, Great Britain, Italy, Morocco, Portugal, Sicilia, Spain, Switzerland but naturalised in Austria, Czechia, Denmark and Sweden. But GBIF shows it has extended to parts of North America, Australia and New Zealand.
Two garden species of Helleborus. Left, Helleborus x glandorfensis, Right H. niger (Christmas Rose). Note the prominent nectaries. In the H. niger image the stamens have withered. Photos: John Grace.
There are many other species of Helleborus in the world but, apart from H. niger only three are described in Stace’s New Flora of the British Isles. They are H. argutifolius (Corsican Hellebore), H. viridis (Green Hellebore) and H. orientalis (Lenten-Rose). Both the native H. viridis and the neophyte H. orientalis are occasionally recorded in the wild, but are more frequent in the south of Britain. The familiar cottage-garden plant Christmas Rose is H. niger; but despite being much-loved, it is an alien, having been introduced many years ago from its native range (Austria, Germany, Italy, Switzerland, and the former Yugoslavia).
I have been looking in garden centres for the Stinking Hellebore. They have the traditional Christmas Rose and some very showy hybrids, but no Stinking Hellebore. However, a few days ago I found the Stinking one in the Tesco Supermarket at Hermiston Gait in Edinburgh. There were only three plants, so hurry whilst stocks last.
References
Rice G (2002) Hellebores. RHS Wisley Handbooks. Cassells, London.
Stewart A et al. (1994) Scarce Plants in Britain. JNCC, Peterborough.
©John Grace
Botany in Scotland 
Dear John, I came across your piece on the Hellebore whilst searching for locations of the plant. I would like to photograph the Hellebore as part of a project I am doing, loosely based on the ancient uses of the plant; the hellebore was apparently used to cure insanity. I would like to photograph Helleborus Niger. Does this particular plant come in white and black variations? Preferably I would like to photograph it in the ground, either wild or cultivated. I use a large format camera on a tripod. Do you have any idea as to where I might be able to find them growing in Scotland? I am based in Glasgow.
Thank you so much for your time.
Very best,
Jonathan
LikeLike