Hellebores: Christmas rose and Lenten rose
In short: the name hellebore mainly covers two plants. The Christmas rose (Helleborus niger) is white, flowers from winter onwards and can be temperamental. The Lenten rose (Helleborus × hybridus), in a range of colours, flowers from late winter into spring and practically grows itself. Both like partial shade, are planted from autumn to spring and are toxic in all their parts. The old leaves of the Lenten rose are cut in winter to limit leaf spot.
When everything else in the garden is asleep, hellebores flower. Their blooms withstand frost and snow and last for weeks. They are true Belgian garden plants: hardy, made for the shade of trees, and two species are even native. You still need to know which one you are buying, because the Christmas rose and the Lenten rose don't need quite the same care.
Christmas rose and Lenten rose: two different plants
The Royal Horticultural Society (RHS) divides hellebores into two groups: those that are easy to grow, including the Lenten rose, the Corsican hellebore (H. argutifolius) and the stinking hellebore (H. foetidus), and those that need more care, including the Christmas rose.
| Christmas rose | Lenten rose | |
|---|---|---|
| Botanical name | Helleborus niger | Helleborus × hybridus (formerly sold as H. orientalis) |
| Flowers | White, sometimes flushed pink, bowl-shaped, up to 8 cm | White, pink, purple, almost black, yellow, often speckled, nodding |
| Flowering | Midwinter to early spring; from the festive season for some selections | Late winter into spring |
| Old leaves | Before flowering, remove only damaged leaves | All cut back to the ground in winter |
| Preferred soil | Neutral to alkaline, moist but well drained | Rich in organic matter, neither too dry nor waterlogged |
| Difficulty | More temperamental | Easy and long-lived |
The name "Christmas rose" often promises more than it delivers. In our climate, the wild species tends to flower after the holidays. Plants sold in flower for Christmas are earlier selections, often grown under cover to bring their flowering forward. The RHS notes of one of them that it is often "forced" to flower earlier.
Not roses, and not petals
Despite their names, hellebores are not roses. They belong to the buttercup family, Ranunculaceae, like buttercups, Japanese anemones and columbines.
Another surprise: what look like petals are sepals, the outer layer that protects the bud in most flowers. The true petals are reduced to small nectar-holding cups at the centre of the flower. That explains why the flowers last so long: unlike most petals, the sepals are long-lived and often stay on the plant for months after flowering. A "faded" hellebore flower can therefore stay decorative for weeks.
These winter flowers are valuable for insects: the RHS lists many hellebores as plants for pollinators.
Belgium's wild hellebores
Two hellebores are native to Belgium, according to the Nouvelle Flore de la Belgique as cited by Meise Botanic Garden:
- the stinking hellebore (Helleborus foetidus), whose finely divided leaves give off an unpleasant smell when crushed, with clusters of pale green bells edged with purple;
- the green hellebore (Helleborus viridis subsp. occidentalis), with fragrant pale green flowers, whose leaves usually do not last through the winter.
Both have a fairly restricted range in Belgium, and both also escape from gardens. The Christmas rose, by contrast, is a plant of the Alps: it is considered a garden escape, locally naturalised in the 19th century and earlier.
The stinking hellebore is an excellent garden plant for darker corners: the RHS says it prefers deeper shade than the others.
Where and when to plant hellebores
When? From autumn to spring, avoiding the dry summer months. Hellebores are usually sold in flower, so you can choose the colour.
Where? Most like light or dappled shade, with some sun, in soil that is neither very dry nor waterlogged. The ideal spot is at the foot of a deciduous tree or shrub: sun in winter, when they flower, and shade in summer. The Christmas rose prefers a cool, sheltered spot in light shade with free-draining soil: on heavy or poorly drained ground, plant it in a raised bed or a pot.
How? According to the RHS:
- Plant at the same level as in the original pot: hellebores don't like being planted too deep.
- Space them 35 to 45 cm apart, and about 60 cm for the stinking hellebore.
- Mulch with at least 5 cm of organic matter, from late autumn to late winter, leaving a gap around the base of the stems.
- Water regularly in the first year, then only during dry spells.
Once established, hellebores don't like being disturbed: let them form large clumps. In the ground, they seldom need feeding. A compost mulch every autumn is enough.
The Christmas rose bought in a pot for the holidays
This is often how people discover it: a pot in flower, bought in December to decorate the table or the doorstep. A few rules for keeping it:
- indoors, keep it cool and close to the light. A heated room shortens flowering;
- after flowering, gradually reacclimatise it to outdoor conditions before planting it in the garden, as the RHS advises for forced hellebores;
- in a pot, use a container only slightly larger and a free-draining compost, and water regularly, as it dries out quickly. The RHS notes that the Christmas rose actually does best kept permanently in a pot, which can be moved under cover in winter.
For the rest of the Christmas plants, from poinsettia to holly, see our 15 Christmas plant myths checked.
Cutting the old leaves: when and which
This is the only real maintenance job, and it depends on the species.
Lenten rose and hybrids: their flowers come up from the ground on stems separate from the leaves. So you can cut all the old leaves back to the ground in winter, before flowering. The flowers are shown off better and, above all, you limit leaf spot, a disease that passes from old leaves to new ones. The plantsman Graham Rice, on the RHS website, considers November the best time; the RHS growing guide says late winter or early spring. In practice: any time between November and the appearance of the buds.
Christmas rose: the RHS advises confining yourself, before flowering, to removing damaged or spotted leaves, then taking off faded foliage as the flowers appear.
Corsican hellebore, stinking hellebore: in these leafy-stemmed species, flowers and leaves grow on the same stems. Remove diseased leaves in autumn, then the spent flower stems and old leaves after flowering, in late spring.
Propagation: self-sown seedlings and division
Lenten roses, Corsican hellebores and stinking hellebores self-seed very freely. The young plants can be left in place or potted up. But hellebores cross with each other: seedlings do not necessarily look like their parents. Graham Rice even advises cutting the spent flower stems before the pods split, because seedlings that drop into the heart of the clump often make poorer plants.
To reproduce a variety exactly, you need to divide the clump, in early autumn or in spring straight after flowering. The RHS points out that divisions may take a couple of years to flower well, and that the Corsican and stinking hellebores don't divide well: they are better grown from seed.
Diseases: leaf spot and "black death"
Leaf spot (Microsphaeropsis hellebori) is the most common problem: round brown spots on leaves and stems, encouraged by damp. The RHS notes that the Christmas rose is particularly susceptible. Remove affected leaves as soon as you see them.
"Black death" is far more serious. The plant is stunted and distorted, and its leaves develop black streaks and netting along the veins. It is probably caused by a virus, Helleborus net necrosis virus, probably transmitted by the hellebore aphid, although the RHS points out that conclusive proof is still lacking. There is no cure: dig up and destroy the plant without delay. According to the RHS, the Lenten rose is the most affected. When buying, reject any plant with black-streaked leaves.
Toxic from root to flower
Hellebores are poisonous plants. The Meise Botanic Garden leaflet on toxic plants, produced with the Belgian Poison Centre, is unambiguous: in hellebores, the whole plant is very toxic. The RHS, for its part, states that the Christmas rose is harmful if eaten and a skin irritant, for people as well as pets.
Hellebores contain bufadienolides, compounds that act on the heart, and protoanemonin, an irritant common to many members of the buttercup family. In dogs and cats, the American association ASPCA lists drooling, abdominal pain, diarrhoea, colic and depression as signs of poisoning.
A few common-sense rules:
- keep an indoor Christmas rose out of reach of young children and pets;
- don't use it in a table decoration near food;
- wear gloves to cut back or divide it.
Beware of confusing names. The "white hellebore" of old is not a hellebore at all: it is white false hellebore (Veratrum album), a tall plant of mountain meadows from another family, and highly toxic too. Serious poisonings happen when it is mistaken for yellow gentian, whose roots are used to make liqueurs, or for wild garlic, as in several published cases. The Lyon poison centre described another serious case in 2023, caused by a "homemade" gentian drink actually prepared with Veratrum.
A plant steeped in history
The Christmas rose's species name, niger ("black"), is surprising for a white flower: it refers to the colour of its roots. The name "hellebore" comes from Greek; it is often linked to words meaning "to injure" and "food", an allusion to its toxicity.
In antiquity, "black hellebore" was used as a violent purgative and was believed to cure madness. The medicinal garden of the Royal College of Physicians in London recalls that, according to Pliny, the seer and physician Melampus used it to cure people suffering from madness, hence another old name for the plant, melampodium. Modern medicine has abandoned these uses.
The legend is gentler. A tradition recorded by garden historians tells of a young shepherdess, Madelon, who wept because she had no gift for the child in Bethlehem; where her tears fell in the snow, an angel made a Christmas rose bloom.
Good companions
At the foot of deciduous trees and shrubs, hellebores combine well with other shade plants that take over in summer, such as hardy geraniums, Japanese anemones or ferns. In spring, snowdrops and crocuses flower alongside them. And for the other jobs of the season, see December in the garden.
Sources
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Czerwiec, A., Paret, N., Guitton, J., & Cohen, S. (2023). Intoxication par vératre : description d'un cas grave et identification des alcaloïdes contenus dans la plante. Toxicologie Analytique et Clinique. https://doi.org/10.1016/j.toxac.2023.07.001
Gardens Illustrated. (n.d.). Hellebores: what to know and which to grow. https://gardensillustrated.com/plants/hellebores-what-to-know-and-which-to-grow/
Gilotta, I., & Brvar, M. (2010). Accidental poisoning with Veratrum album mistaken for wild garlic (Allium ursinum). Clinical Toxicology, 48(9), 949-952. https://doi.org/10.3109/15563650.2010.533675
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The Garden History. (2022, 24 December). Christmas roses. https://thegardenhistory.blog/2022/12/24/christmas-roses
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