Hellebore
Hellebore | |
---|---|
19th century illustration of Helleborus niger | |
Scientific classification | |
Kingdom: | Plantae |
Clade: | Tracheophytes |
Clade: | Angiosperms |
Clade: | Eudicots |
Order: | Ranunculales |
Family: | Ranunculaceae |
Subfamily: | Ranunculoideae |
Tribe: | Helleboreae DC. |
Genus: | Helleborus L.[1] |
Species | |
See text |
Commonly known as hellebores (
Despite
Description
The flowers have five petal-like
Taxonomy
The genus was established by Carl Linnaeus in volume one of his Species Plantarum in 1753.[1]
The scientific name Helleborus could derive from the Ancient Greek word ἑλλέβορος (helléboros), the common name for H. orientalis, constructed from ἑλεῖν (heleîn, "to injure") and βορά (borá), "food.".[7][8][9] It is also possibly from Greek, ἄλκη “fawn”, βιβρώσκω (bibrṓskō, “to eat”).[10][unreliable source]
Species and subspecies
Twenty-two species are recognised and divided into six sections.[11] The table below shows the species of the genus Helleborus, give its common name, the area of distribution, an image if available and the meaning of the scientific name.[11][12][13] The cladogram shows the relationship between the different species determined with microbiological methods by Meiners et al. (2011).[11]
Name | Common name | meaning of the scientific name | Distribution area | Color of the flower | Image |
---|---|---|---|---|---|
Subgenus Helleborus | |||||
I. sect. Griphopus Spach em. Schiffner | gryphon + foot | ||||
Helleborus foetidus L. 1753 |
stinking hellebore or setterwort | stinking | SW – M Europe | green, commonly red rim | |
II. sect. Chenopus Schiffner | goose + foot | ||||
Helleborus lividus Aiton 1789 |
lead colored, bluish | Majorca | green | ||
Helleborus argutifolius Viv. 1824 |
Corsican hellebore often H. lividus Aiton subsp. corsicus (BRIQ.) P. FOURN. |
sharp-leafed[14] | Corsica, Sardinia | green, white | |
III. sect. Helleborus [sect. Chionorhodon Spach] |
snow, rose | ||||
Helleborus niger L. 1753 |
Christmas rose or black hellebore | black | Croatia, Slovenia, N Italy, Switzerland, Austria, S Germany | white, later pink | |
subsp. macranthus | white, later pink | ||||
subsp. niger L. | white, later pink | ||||
Subgenus Helleborastrum (Spach) | |||||
IV. sect. Syncarpus Schiffer | with/together + flower (3 flowers fused together) | ||||
Helleborus vesicarius Aucher ex Boiss. 1841 |
SE Turkey, NW Syria | red | |||
V. sect. Dicarpon Ulbrich | two + flower (2 flowers fused together) | ||||
Helleborus thibetanus Franch. 1885 |
China | pink | |||
VI. sect. Helleborastrum Spach | hellebore + resembling | ||||
Helleborus abruzzicus M.Thomsen, McLewin & B.Mathew |
Abruzzo | middle Italy | whitish, greenish | ||
Helleborus atrorubens Waldst. & Kit. 1812 |
dark, red | Slovenia, N Croatia, Bosnia, former Yugoslavia |
reddish, purple | ||
Helleborus bocconei Ten. 1823 |
Botanist Paolo Boccone | S Italy, Sicily | white | ||
Helleborus croaticus Martinis 1973 |
from Croatia | NE Croatia | reddish violet | ||
Helleborus cyclophyllus (A.Braun) Boiss. 1867 |
Circle, leafs | Greece, Macedonia, Albania, Bulgaria | green, light green, whitish | ||
Helleborus dumetorum Waldst. & Kit. ex Willd. 1809 |
Slovenia, Hungary, Croatia, Romania, Austria, | green to white | |||
Helleborus liguricus M.Thomsen, McLewin & B.Mathew |
from Liguria | Italy (Ligura, Tuscany) | green to white | ||
Helleborus multifidus Vis. |
multiple segmented | Croatia, Herzegovina | green | ||
subsp. hercegovinus | from Herzegovina | Montenegro, Hercegovina | yellow-green | ||
subsp. istriacus | from Istria | NE Italy, Croatia, Bosnia, Montenegro | green | ||
subsp. multifidus | multiple segmented | Albania and former Yugoslavia | |||
Helleborus odorus Waldst. & Kit. ex Willd. 1809 |
odorant | S- and SE Europe with focus at the Balkans |
green bis yellowish-green | ||
subsp. odorus L. | odorant | ||||
Helleborus orientalis Lam. 1789 |
Lenten rose, Lenten hellebore, oriental hellebore | from the east | N Turkey, Bulgaria, Ukraine, Georgia, Caucasus | white, yellowish, pink | |
subsp. abchasicus (A. Braun) Mathew |
from Abchasia |
Georgia | pink, reddish | ||
subsp. guttatus (A. Braun & Sauer) Mathew |
dotted | ||||
subsp. orientalis | H. caucasicus, H. kochii | from the east | occasionally used for ssp. gutatus + abchasicus | reddish | |
Helleborus purpurascens Waldst. & Kit. 1802 |
purple / red | Hungary, Slovakia, Poland, Romania | violet, brown | ||
Helleborus torquatus Archer-Hind 1884 |
adorned with a necklet | Croatia, Bosnia, Serbia, Montenegro | green, violet | ||
Helleborus viridis L. 1753 |
green hellebore or bear's-foot | green | Austria, N Italy, Switzerland, S Germany | green | |
subsp. occidentalis 1869 |
from the west | N Spain, SW France (France, Germany, Great Britain naturalised) | green |
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Cladogram of evolutionary lines in Helleborus from Meiners et al.(2011) [11] |
Caulescent species
These four species have leaves on their flowering stems (in H. vesicarius the stems die back each year; it also has basal leaves).
- Helleborus argutifolius – Corsican hellebore
- Helleborus foetidus – stinking hellebore or setterwort
- Helleborus lividus
- Helleborus vesicarius
Acaulescent (stemless) species
These species have basal leaves. They have no true leaves on their flower stalks (although there are leafy bracts where the flower stalks branch).
- Helleborus atrorubens
- Helleborus croaticus
- Helleborus cyclophyllus
- Helleborus dumetorum
- Helleborus abruzzicus
- Helleborus liguricus
- Helleborus bocconei
- Helleborus multifidus
- Helleborus multifidus subsp. hercegovinus
- Helleborus multifidus subsp. istriacus
- Helleborus multifidus subsp. multifidus
- Helleborus niger – Christmas rose or black hellebore
- Helleborus niger subsp. macranthus (syn. H. niger major)
- Helleborus niger subsp. niger
- Helleborus odorus
- Helleborus odorus subsp. laxus
- Helleborus odorus subsp. odorus
- Helleborus orientalis – Lenten rose, Lenten hellebore, oriental hellebore (N.B. most of the Lenten hellebores in gardens are now considered to be H. × hybridus)
- Helleborus orientalis subsp. abchasicus (syn. H. abchasicus)
- Helleborus orientalis subsp. guttatus
- Helleborus orientalis subsp. orientalis (syn. H. caucasicus, H. kochii)
- Helleborus purpurascens
- Helleborus thibetanus (syn. H. chinensis)
- Helleborus torquatus
- Helleborus viridis - green hellebore or bear's-foot
- Helleborus occidentalis (formerly H. viridis subsp. occidentalis)
Other species names (now considered invalid) may be encountered in older literature, including H. hyemalis, H. polychromus, H. ranunculinus, H. trifolius.
Hellebore hybrids
Recent breeding programmes have also created double-flowered and anemone-centred plants. Ironically, doing this is actually reversing the evolutionary process in which hellebores' true petals had been modified into nectaries; it is usually these nectaries which become the extra petals in double, semi-double and anemone-centred flowers. Double-flowered hellebores[15] provide a very interesting variation to the standard hellebore. They are generally easy to maintain and share the same planting conditions as the standard hellebore.
Semi-double flowers have one or two extra rows of petals; doubles have more. Their inner petals are generally very like the outer ones in colour and patterning. They are often of a similar length and shape, though they may be slightly shorter and narrower, and some are attractively waved or ruffled. By contrast, anemone-centred flowers have, cupped within the five normal outer petals, a ring of much shorter, more curved extra petals (sometimes trumpet-shaped, intermediate in appearance between petals and nectaries), which may be a different colour from the outer petals. These short, extra petals (sometimes known as "petaloids") drop off after the flower has been pollinated, leaving an apparently single flower, whereas doubles and semi-doubles tend to retain their extra petals after pollination.
Interspecific hybrids
Gardeners and
The following hellebore species and cultivars have gained the Royal Horticultural Society's Award of Garden Merit:
Distribution
Various species of this genus originated in Europe and Asia.[23] The greatest concentration of species occurs in the Balkans. One atypical species (H. thibetanus) comes from western China; another atypical species (H. vesicarius) inhabits a small area on the border between Turkey and Syria.
Pests and diseases
Insects
Phytomyza hellebori
More commonly known as the Hellebore leaf miner, Phytomyza hellebori is a small fly that infests only the H. foetidus plants in the Hellebore genus. The leaf miner fly digs tunnels into the leaves of the H. foetidus. The tunnels create brownish-black blotches on the plant. These later turn into a nesting ground where the flies lay their eggs. With time, the leaves turn a brownish-white along where the tunnels were dug. The larvae start to eat the inside of the leaves in August, and damage develops from the late summer to the early spring, with heavy attacks leaving the foliage disfigured by spring.[24]
To control heavy infestations, the leaves can be removed and destroyed during the winter months before the adult flies emerge. Insecticides can be used with limited effectiveness in controlling larvae and fly populations in the plant. Insecticides may harm non-leaf miner flies if applied during the hellebore's flowering period.[24]
Macrosiphum hellebori
Macrosiphum hellebori, commonly known as 'Hellebore aphid' or 'greenfly', is a sap-feeding aphid that infests the flowers and foliage of hellebore plants. The whitish-green aphids are about 2–4 millimetres (3⁄32–5⁄32 inch) long and form dense colonies on hellebores, coating them with a honeydew that can lead to the growth of sooty mold on the leaves and flowers of the hellebore. This species of aphid only affects hellebores and is most active in March and April when the hellebores are flowering and when few aphid predators are around, though they may infest during any time of the year.[25][26]
Aphids start their feeding from the outside the flowers, beginning at the leaves and then moving towards the flower petals of the hellebore. As the hellebore beings to open, the aphids try to move into the flower. The aphids then feed on the inner parts of the plant as well as the young stems and shoots. As the population grows, the aphids eventually eat the remaining parts of the plant, such as older leaves, for food.[26]
Aphid infestations can be controlled through persistent squashing of the aphids manually or by using insecticides. It is not recommended to spray flowering hellebores as it may harm the non-aphid pollinating insects.[25]
Diseases
Botrytis cinerea
To treat the infected plant, the first step is to remove infected and dying leaves, buds, and flowers immediately along with any other dead plant materials around the hellebore. The next step is to reduce the humidity around the plant by improving the ventilation and ensuring the plants are not overcrowded.[27]
Coniothyrium hellebori
Coniothyrium hellebori is a fungus that causes the most common fungal disease for helleborus species known as Hellebore black spot or leaf spot. The disease is most common not only in botanical and ornamental gardens but also in hellebore nurseries as well. Visible symptoms include blackish-brown spots that often appear as rings on the leaf blade or at the margins of the leaf. The spots continue to grow larger as the disease progresses, retaining an elliptical or circular shape and turning a dark brown or black color. The spots grow until they infect the whole leaf. Petioles and flowers can also be infected, but the disease is primarily seen in the leaves. The symptoms become visible in the spring and worsen with time.[28]
The small black fruiting bodies which carry the spores,
Helleborus net necrosis virus
Helleborus net necrosis virus (HeNNV), also known as Hellebore black death, is an RNA virus that can cause serious disease in Hellebore plants by stunting or deforming the plant as it grows. The disease marks the leaves of the hellebores with black streaks, often following the veins of the leaf, and creating ring patterns. It can also mark the sepals and flowers with black spots or streaks but does not always do so. When symptoms are severe, new leaves have limited growth before dying off.[29] The most seriously affected in the UK is H. orientalis, but all hellebores are susceptible to the disease.[30] The most effective method of treatment against black death is to dig up and destroy all infected plants immediately. Many viruses are not transmitted through seeds, so it is possible to raise new disease resistant plants this way.[30]
Pseudomonas viridiflava
Horticulture
Hellebores are widely grown in
The so-called Christmas rose (H. niger), a traditional cottage garden favourite, bears its pure white flowers (which often age to pink) in the depths of winter; large-flowered cultivars are available, as are pink-flowered and double-flowered selections.
The most popular hellebores for garden use are H. orientalis and its colourful hybrids, H. × hybridus (Lenten rose). In the northern hemisphere, they flower in early spring, around the period of Lent, and are often known as Lenten hellebores, oriental hellebores, or Lenten roses. They are excellent for bringing early colour to shady herbaceous borders and areas between deciduous shrubs and under trees.
The cultivar Walberton's Rosemary='Walhero' (sometimes listed under H. × hybridus) has won the Royal Horticultural Society's Award of Garden Merit.[33]
Toxicity
All helleborus plants are toxic, and all parts of the helleborus plant are toxic.[34][35] Hellebore poisoning is rare, but it does occur.[34] Hellebore plants are usually left alone by animals such as deer and rabbits because the leaves of the plant produce poisonous
Poisonings occur through ingestion or handling. Hellebore plants should not be ingested as poisoning cases are most severe when the plants are eaten. This is especially true when hellebores are eaten in large quantities.[35] Symptoms of ingestion include: burning of the mouth and throat, salivation, vomiting, abdominal cramping, diarrhea, nervous symptoms, and possibly depression. Consuming large quantities of hellebore plants can be fatal.[35] Toxic cardiac glycosides occur in the roots. High levels of ranunculin and protoanemonin, especially in the leaves and sap, also contribute to symptoms after ingestion.[34]
Dermatitis may also occur from handling the hellebore plants without protection. This is typically caused by the ranunculin and protoanemonin found on the outside of the plant, including the leaves, stem, flower, and sap. The poison on the outside of the plant causes irritation and burning sensations on the skin.[34][35] When collecting seeds from hellebore plants, it is recommended to wait for the pods to dry and shake them out into a container or onto the ground to collect. Attempts to remove the seeds by hand exposes skin to the potent toxins in the sap of the hellebore, which can increase the damage done to the skin. Small or minimal exposure to the toxins should only cause a mild irritation to the skin, and the affliction should only last for a few minutes. If the burning persists or intensifies, it is recommended to wash the affected areas thoroughly to remove the toxins and see a doctor.[34][35]
The species historically known as "Black hellebore" cause
Uses
In the early days of medicine, two kinds of hellebore were recognized: black hellebore, which included various species of Helleborus, and white hellebore, now known as
Despite its toxicity, "black hellebore" was used by the Greek and Romans to treat paralysis, gout and other diseases, more particularly insanity.[42]
Culture
H. niger is commonly called the Christmas rose, due to an old legend that it sprouted in the snow from the tears of a young girl who had no gift to give the Christ Child in Bethlehem.[43]
In
During the Siege of Kirrha in 585 BC, hellebore was reportedly used by the Greek besiegers to poison the city's water supply. The defenders were subsequently so weakened by diarrhea that they were unable to defend the city from assault.[45]
In a fit of madness induced by Hera, Heracles killed his children by Megara. His madness was cured using hellebore.[46]
Gallery
Species
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H. dumetorum (Hecken-Nieswurz)
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Jardin des Plantes de Paris)
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Innsbruck Botanical Garden
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H. niger with fruits and flowers in two different stages
Hybrids
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Double hellebore, dark red
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Double white and pink picotee hellebore
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Double pink hellebore with dark blotching
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Double white hellebore with pink spotting
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Double pink hellebore with darker pink veining
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Double white hellebore hybrid 'Betty Ranicar'
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Yellow double hellebore
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"Blue-black" double hellebore
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Double pink hellebore with dark venation
-
Seed pods swell
See also
References
- ^ a b Linnaeus, Carolus (1753). "Tomus I". Species Plantarum (in Latin). Vol. 1. Stockholm: Laurentii Salvii. p. 557.
- ^ "Definition of HELLEBORE". www.merriam-webster.com. 24 February 2024.
- ^ "Guide to Growing Hellebore Flowers". Lifehack. Retrieved 15 June 2023.
- ^ a b "Hellebores' roses of winter - Yates". www.yates.co.nz.
- ^ "Christmas Rose". Retrieved 18 June 2014.
- ^ Herrera 2005
- ^ "Helleborus niger - Christmas Rose". Retrieved 9 June 2014.
- OCLC 461974285.
- ^ Bailly, Anatole. "Greek-french dictionary online". www.tabularium.be. Retrieved 6 January 2018.
- ^ "hellebore - Wiktionary". en.wiktionary.org. Retrieved 2 March 2021.
- ^ .
- .
- .
- ISBN 978-1845337315.
- ^ "Double Hellebores". Retrieved 9 October 2007.
- ^ "ashwoodnurseries.com". ashwoodnurseries.com. Retrieved 2 August 2012.
- ^ "Hellebores: Ashwood Garden Hybrids". Ashwoodnurseries.com. Retrieved 2 August 2012.
- ^ "RHS Plant Selector Helleborus argutifolius AGM / RHS Gardening". Apps.rhs.org.uk. Archived from the original on 18 December 2019. Retrieved 2 August 2012.
- ^ "RHS Plant Selector Helleborus foetidus AGM / RHS Gardening". Apps.rhs.org.uk. Archived from the original on 4 February 2012. Retrieved 2 August 2012.
- ^ "RHS Plant Selector Helleborus lividus AGM / RHS Gardening". Apps.rhs.org.uk. Archived from the original on 18 December 2019. Retrieved 2 August 2012.
- ^ "RHS Plant Selector Helleborus niger AGM / RHS Gardening". Apps.rhs.org.uk. Archived from the original on 8 December 2013. Retrieved 2 August 2012.
- ^ "RHS Plant Selector Helleborus × sternii Blackthorn Group AGM / RHS Gardening". Apps.rhs.org.uk. Retrieved 2 August 2012.[permanent dead link]
- ^ "About the Helleborus". Archived from the original on 24 July 2014. Retrieved 18 July 2014.
- ^ a b "Hellebore leaf miner". Royal Horticulture Society.
- ^ a b "Hellebore Aphid". Royal Horticultural Society.
- ^ .
- ^ a b "Grey Mould". Royal Horticulture Society.
- ^ .
- S2CID 29088363.
- ^ a b "Hellebore black death". Royal Horticultural Society.
- ^ S2CID 7467719.
- ^ "Nursery owner extols many virtues of hellebores". Archived from the original on 28 May 2014. Retrieved 28 May 2014.
- ^ "Helleborus Walberton's Rosemary='Walhero'". www.rhs.org. Royal Horticultural Society. Retrieved 6 August 2020.
- ^ a b c d e "Helleborus niger - Christmas Rose". Cornell University, College of Agriculture and Life Sciences.
- ^ a b c d e "Helleborus orientalis". NC State University.
- ^ Cary, Bill (24 March 2013). "Hellebores -- deer resistant and made for shade". Gannett Co., Inc. The Journal News; White Plains, N.Y.
- ^ a b Chisholm, Hugh, ed. (1911). . Encyclopædia Britannica. Vol. 13 (11th ed.). Cambridge University Press. pp. 235–236.
- ^ Olson, Kent R., Poisoning & Drug Overdose, p312 at Google Book Search, accessed 12 January 2009
- ^ a b Smolinske, Susan C., Toxicity of Houseplants, pp38, 153 at Google Book Search, accessed 12 January 2009
- ^ Olson, Kent R, Poisoning & Drug Overdose, p309 at Google Book Search, accessed 12 January 2009
- ^ "Vascular Plant Families and Genera - List of Genera in Melanthiaceae". mobot.org. Retrieved 21 October 2010.
- ^ "hellebore". merriam-webster.com. Retrieved 18 June 2014.
- ^ "February 2013 Plant of the Month: Hellebore". Retrieved 9 June 2014.
- PMID 23115576.
- ^ "Hellebore make for an enchanting addiction". Retrieved 18 June 2014.
- ^ "Heracles Heracles • Facts and Information on the Greek Hero Heracles".
- Herrera, C. M. (1 September 2005). "Post-floral perianth functionality: contribution of persistent sepals to seed development in Helleborus foetidus (Ranunculaceae)". American Journal of Botany. 92 (9): 1486–1491. S2CID 9062980.
- Orphan reference: Graham Rice & Elizabeth Strangman, The Gardener's Guide to Growing Hellebores, David & Charles/Timber Press (1993) ISBN 0-7153-9973-X
- Orphan reference: Brian Mathew, Hellebores, Alpine Garden Society (1989) ISBN 0-900048-50-6
External links
- Media related to Helleborus at Wikimedia Commons
- Data related to Helleborus at Wikispecies
- A French hellebore enthusiast's non-commercial site
- The National Collection of Hellebore species and hybrids, Hazles Cross Farm Nursery (Staffordshire, UK) contains all known species plus hundreds of garden hybrids
- Flora Europaea: Helleborus
- Hellebores.org: A comprehensive online resource on the genus Helleborus
- National collection of Hellebores
- RHS plant pathology report on 'Hellebore Black Death' disease (pdf)
- Growing Guide