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{{Taxobox
| color = lightgreen
| name = Hellebore
| image = Helleborus niger .JPG
| image_width = 240px
| image_caption = ''Helleborus niger'', the so-called "Christmas rose", in the wild
| regnum = [[Plant]]ae
| divisio = [[Flowering plant|Magnoliophyta]]
| classis = [[Magnoliopsida]]
| ordo = [[Ranunculales]]
| familia = [[Ranunculaceae]]
| genus = '''''Helleborus'''''
| genus_authority = [[Carolus Linnaeus|L.]]
| subdivision_ranks = [[Species]]
| subdivision =
| species =
See text
}}
[[Image:Illustration Helleborus niger0.jpg|thumb|19th century illustration of ''Helleborus niger'']]
[[Image:HelleborusFoetidus-plant.jpg|thumb|right|''Helleborus foetidus'' has handsome, deeply divided evergreen leaves]]
[[Image:Helleborus foetidus0.jpg|thumb|right|The small green flowers of ''H. foetidus'' often have a purple edge to each 'petal']]
[[Image:Helleborus lividus corsicus0.jpg|thumb|right|The Corsican hellebore, ''Helleborus argutifolius'' (formerly ''H. lividus'' subsp. ''corsicus'' or ''H. corsicus'')]]
'''''Helleborus''''' is a genus of approximately 20 species (ongoing fieldwork may see this figure change) of [[herbaceous]] [[perennial]] [[flowering plants]] in the family [[Ranunculaceae]], within which it gave its name to the [[tribe (biology)|tribe]] of [[Helleboreae]].
==Distribution and description==
The genus is native to much of [[Europe]], from western [[Britain]], [[Spain]] and [[Portugal]], eastward across the [[Mediterranean region]] and central Europe into [[Romania]] and [[Ukraine]], and along the north coast of [[Turkey]] into the [[Caucasus]]. 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]].
The flowers have five "[[petal]]s" (actually [[sepals]] or [[tepal]]s) surrounding a ring of small, cup-like [[nectaries]] (petals modified to hold [[nectar]]). The sepals do not fall as petals would, but remain on the plant, sometimes for many months. Recent research in Spain suggests that the persistent [[calyx]] contributes to the development of the [[seed]]s (Herrera 2005).
Although the flowers of some species may resemble [[dog rose|wild roses]] (and despite some of their common names, such as "'''Christmas rose'''" and "'''Lenten rose'''"), hellebores do not belong to the [[rose]] family ([[Rosaceae]]).
==Species and subspecies==
===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''<!-- NB for Editors: Please keep hybrid × signs outside inverted commas, otherwise they will appear italicised on certain browsers -->)
**''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]]''
*''[[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''.
==Garden use==
Hellebores are widely grown in gardens for decorative purposes, as well as for their [[herbalism|purported medicinal abilities]] and uses in [[witchcraft]]. They are particularly valued by gardeners for their winter and early spring flowering period; the plants are surprisingly [[frost]]-resistant and many are [[evergreen]]. Many species of hellebore have green or greenish-purple flowers and are of limited garden value, although Corsican hellebore (''H. argutifolius''), a robust plant with pale green, cup-shaped flowers and attractive leathery [[foliage]], is widely grown. So is stinking hellebore or setterwort (''H. foetidus''), which has drooping clusters of small, pale green, bell-shaped flowers, often edged with maroon, which contrast delightfully with its dark [[evergreen]] foliage. ''H. foetidus'' 'Wester Flisk', with red-flushed flowers and flower stalks, is becoming popular, as are more recent selections with golden-yellow foliage.
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 [[cultivar]]s are available, as are pink-flowered and double-flowered selections.
The most popular hellebores for garden use, however, are undoubtedly ''H. orientalis'' and its colourful [[hybrid]]s (''H.'' × ''hybridus''). 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 border]]s and areas between [[deciduous]] [[shrub]]s and under trees.
===Hellebore hybrids===
<!-- NB for editors: Please keep hybrid × signs outside inverted commas, otherwise they will appear italicised on certain browsers -->
[[Image:Hellebore flowers.jpg|thumb|left|Hellebore species and hybrids: ''Helleborus viridis'' (top left); ''H. foetidus'' (top right) with cross-section; flowers of various specimens of ''H.'' × ''hybridus'', including doubles]]
[[Image:Hellebore flower - greenish white P.2005.04.04.jpg|thumb|right|A flower of ''H.'' × ''hybridus'' with olive-green nectaries visible behind the stamens]]
[[Image:Lenteroos rood plant.jpg|thumb|right|''H.'' × ''hybridus'' in a garden]]
Hybridising (deliberate and accidental) between ''H. orientalis'' and several other closely-related species and subspecies has vastly improved the colour-range of the flowers, which now extends from slate grey, near-black, deep purple and plum, through rich red and pinks to yellow, white and green. The outer surface of the sepals is often green-tinged, and as the flower ages it usually becomes greener inside and out; individual flowers often remain on the plant for a month or more. The inner surface of each sepal may be marked with veins, or dotted or blotched with pink, red or purple. "Picotee" flowers, whose pale-coloured sepals have narrow margins of a darker colour, are much sought-after, as are those with dark nectaries which contrast with the outer sepals.
Recent breeding programmes have also created double-flowered and anemone-centred plants. Ironically, doing this is actually reversing the [[evolution]]ary 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.
Semi-double flowers have one or two extra rows of petals; doubles have more. Their inner petals are generall
y 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 [[pollination|pollinated]], leaving an apparently single flower, whereas doubles and semi-doubles tend to retain their extra petals after pollination.
===Interspecific hybrids===
Gardeners and [[nursery (horticulture)|nurserymen]] have also created hybrids between less closely-related species. The earliest was probably ''H.'' × ''nigercors'', a cross between ''H. niger'' and ''H. argutifolius'' (formerly ''H. lividus'' subsp. ''corsicus'' or ''H. corsicus'', hence the name) first made in 1931. ''H.'' × ''sternii'', a cross between ''H. argutifolius'' and ''H. lividus'', first exhibited in 1947, is named after the celebrated British [[plantsman]] Sir Frederick Stern. ''H.'' × ''ballardiae'' (''H. niger'' crossed with ''H. lividus'') and ''H.'' × ''ericsmithii'' (''H. niger'' crossed with ''H.'' × ''sternii'') similarly commemorate the noted British nursery owners Helen Ballard and Eric Smith. In recent years, Ashwood Nurseries (of [[Kingswinford]] in the English [[Midlands]]), already well-known for its Ashwood Garden Hybrids (''H.'' × ''hybridus'' singles, semi-doubles, doubles and anemone-centres), has created interesting hybrids between ''H. niger'' and ''H. thibetanus'' (called ''H.'' 'Pink Ice'), and between ''H. niger'' and ''H. vesicarius'' (called ''H.'' 'Briar Rose'). The gardenworthiness of these hybrids has still to be proven.
==Folklore==
Several [[legend]]s surround the hellebore; in witchcraft it is believed to have ties to [[summon]]ing [[demon]]s. ''Helleborus 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 [[Child Jesus|Christ child]] in [[Bethlehem]]. In [[Ancient Greece|Greek]] [[mythology]], [[Melampus]] of [[Pylos]] used hellebore to save the daughters of the king of [[Argos]] from a madness, induced by [[Dionysus]], that caused them to run naked through the city, crying, weeping, and screaming.
During the [[First Sacred War|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.
Some historians believe that [[Alexander the Great]] [[Alexander the Great#Death|died because of a hellebore overdose]], when he took it as medication.
==References and External links==
{{commonscat|Helleborus}}
*[http://rbg-web2.rbge.org.uk/cgi-bin/nph-readbtree.pl/feout?FAMILY_XREF=&GENUS_XREF=Helleborus&SPECIES_XREF=&TAXON_NAME_XREF=&RANK=species Flora Europaea: ''Helleborus'']
*[http://www.efloras.org/florataxon.aspx?flora_id=2&taxon_id=200008012 Flora of China: ''Helleborus'']
*Graham Rice & Elizabeth Strangman, ''The Gardener's Guide to Growing Hellebores'', David & Charles/Timber Press (1993) ISBN 0-7153-9973-X
*Brian Mathew, ''Hellebores'', Alpine Garden Society (1989) ISBN 0-900048-50-6
*Herrera, C. M. (2005). Post-floral perianth functionality: contribution of persistent sepals to seed development in ''Helleborus foetidus'' (Ranunculaceae). ''Amer. J. Bot.'' 92: 1486-1491 [http://www.amjbot.org/cgi/content/abstract/92/9/1486 abstract].
* [http://www.hellebore.com/ Garden writer Graham Rice's hellebore site]
* [http://www.hellebores.org Hellebores.org: A comprehensive online resource on the genus ''Helleborus'']
* [http://www.rhs.org.uk/learning/research/Sciencereport/Hellebore.pdf RHS plant pathology report on 'Hellebore Black Death' disease (pdf)]
* [http://phengels.club.fr/Cata
logueHelleborus.html A French hellebore enthusiast's non-commercial site]
==See also==
*[[Christmas flowers]]
[[Category:Ranunculaceae]]
[[Category:Witchcraft]]
[[Category:Abortifacients]]
[[Category:Christmas plants]]
[[Category:Garden plants]]
[[Category:Flowers]]
[[Category:Horticulture]]
| color = lightgreen
| name = Hellebore
| image = Helleborus niger .JPG
| image_width = 240px
| image_caption = ''Helleborus niger'', the so-called "Christmas rose", in the wild
| regnum = [[Plant]]ae
| divisio = [[Flowering plant|Magnoliophyta]]
| classis = [[Magnoliopsida]]
| ordo = [[Ranunculales]]
| familia = [[Ranunculaceae]]
| genus = '''''Helleborus'''''
| genus_authority = [[Carolus Linnaeus|L.]]
| subdivision_ranks = [[Species]]
| subdivision =
| species =
See text
}}
[[Image:Illustration Helleborus niger0.jpg|thumb|19th century illustration of ''Helleborus niger'']]
[[Image:HelleborusFoetidus-plant.jpg|thumb|right|''Helleborus foetidus'' has handsome, deeply divided evergreen leaves]]
[[Image:Helleborus foetidus0.jpg|thumb|right|The small green flowers of ''H. foetidus'' often have a purple edge to each 'petal']]
[[Image:Helleborus lividus corsicus0.jpg|thumb|right|The Corsican hellebore, ''Helleborus argutifolius'' (formerly ''H. lividus'' subsp. ''corsicus'' or ''H. corsicus'')]]
'''''Helleborus''''' is a genus of approximately 20 species (ongoing fieldwork may see this figure change) of [[herbaceous]] [[perennial]] [[flowering plants]] in the family [[Ranunculaceae]], within which it gave its name to the [[tribe (biology)|tribe]] of [[Helleboreae]].
==Distribution and description==
The genus is native to much of [[Europe]], from western [[Britain]], [[Spain]] and [[Portugal]], eastward across the [[Mediterranean region]] and central Europe into [[Romania]] and [[Ukraine]], and along the north coast of [[Turkey]] into the [[Caucasus]]. 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]].
The flowers have five "[[petal]]s" (actually [[sepals]] or [[tepal]]s) surrounding a ring of small, cup-like [[nectaries]] (petals modified to hold [[nectar]]). The sepals do not fall as petals would, but remain on the plant, sometimes for many months. Recent research in Spain suggests that the persistent [[calyx]] contributes to the development of the [[seed]]s (Herrera 2005).
Although the flowers of some species may resemble [[dog rose|wild roses]] (and despite some of their common names, such as "'''Christmas rose'''" and "'''Lenten rose'''"), hellebores do not belong to the [[rose]] family ([[Rosaceae]]).
==Species and subspecies==
===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''<!-- NB for Editors: Please keep hybrid × signs outside inverted commas, otherwise they will appear italicised on certain browsers -->)
**''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]]''
*''[[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''.
==Garden use==
Hellebores are widely grown in gardens for decorative purposes, as well as for their [[herbalism|purported medicinal abilities]] and uses in [[witchcraft]]. They are particularly valued by gardeners for their winter and early spring flowering period; the plants are surprisingly [[frost]]-resistant and many are [[evergreen]]. Many species of hellebore have green or greenish-purple flowers and are of limited garden value, although Corsican hellebore (''H. argutifolius''), a robust plant with pale green, cup-shaped flowers and attractive leathery [[foliage]], is widely grown. So is stinking hellebore or setterwort (''H. foetidus''), which has drooping clusters of small, pale green, bell-shaped flowers, often edged with maroon, which contrast delightfully with its dark [[evergreen]] foliage. ''H. foetidus'' 'Wester Flisk', with red-flushed flowers and flower stalks, is becoming popular, as are more recent selections with golden-yellow foliage.
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 [[cultivar]]s are available, as are pink-flowered and double-flowered selections.
The most popular hellebores for garden use, however, are undoubtedly ''H. orientalis'' and its colourful [[hybrid]]s (''H.'' × ''hybridus''). 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 border]]s and areas between [[deciduous]] [[shrub]]s and under trees.
===Hellebore hybrids===
<!-- NB for editors: Please keep hybrid × signs outside inverted commas, otherwise they will appear italicised on certain browsers -->
[[Image:Hellebore flowers.jpg|thumb|left|Hellebore species and hybrids: ''Helleborus viridis'' (top left); ''H. foetidus'' (top right) with cross-section; flowers of various specimens of ''H.'' × ''hybridus'', including doubles]]
[[Image:Hellebore flower - greenish white P.2005.04.04.jpg|thumb|right|A flower of ''H.'' × ''hybridus'' with olive-green nectaries visible behind the stamens]]
[[Image:Lenteroos rood plant.jpg|thumb|right|''H.'' × ''hybridus'' in a garden]]
Hybridising (deliberate and accidental) between ''H. orientalis'' and several other closely-related species and subspecies has vastly improved the colour-range of the flowers, which now extends from slate grey, near-black, deep purple and plum, through rich red and pinks to yellow, white and green. The outer surface of the sepals is often green-tinged, and as the flower ages it usually becomes greener inside and out; individual flowers often remain on the plant for a month or more. The inner surface of each sepal may be marked with veins, or dotted or blotched with pink, red or purple. "Picotee" flowers, whose pale-coloured sepals have narrow margins of a darker colour, are much sought-after, as are those with dark nectaries which contrast with the outer sepals.
Recent breeding programmes have also created double-flowered and anemone-centred plants. Ironically, doing this is actually reversing the [[evolution]]ary 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.
Semi-double flowers have one or two extra rows of petals; doubles have more. Their inner petals are generall
y 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 [[pollination|pollinated]], leaving an apparently single flower, whereas doubles and semi-doubles tend to retain their extra petals after pollination.
===Interspecific hybrids===
Gardeners and [[nursery (horticulture)|nurserymen]] have also created hybrids between less closely-related species. The earliest was probably ''H.'' × ''nigercors'', a cross between ''H. niger'' and ''H. argutifolius'' (formerly ''H. lividus'' subsp. ''corsicus'' or ''H. corsicus'', hence the name) first made in 1931. ''H.'' × ''sternii'', a cross between ''H. argutifolius'' and ''H. lividus'', first exhibited in 1947, is named after the celebrated British [[plantsman]] Sir Frederick Stern. ''H.'' × ''ballardiae'' (''H. niger'' crossed with ''H. lividus'') and ''H.'' × ''ericsmithii'' (''H. niger'' crossed with ''H.'' × ''sternii'') similarly commemorate the noted British nursery owners Helen Ballard and Eric Smith. In recent years, Ashwood Nurseries (of [[Kingswinford]] in the English [[Midlands]]), already well-known for its Ashwood Garden Hybrids (''H.'' × ''hybridus'' singles, semi-doubles, doubles and anemone-centres), has created interesting hybrids between ''H. niger'' and ''H. thibetanus'' (called ''H.'' 'Pink Ice'), and between ''H. niger'' and ''H. vesicarius'' (called ''H.'' 'Briar Rose'). The gardenworthiness of these hybrids has still to be proven.
==Folklore==
Several [[legend]]s surround the hellebore; in witchcraft it is believed to have ties to [[summon]]ing [[demon]]s. ''Helleborus 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 [[Child Jesus|Christ child]] in [[Bethlehem]]. In [[Ancient Greece|Greek]] [[mythology]], [[Melampus]] of [[Pylos]] used hellebore to save the daughters of the king of [[Argos]] from a madness, induced by [[Dionysus]], that caused them to run naked through the city, crying, weeping, and screaming.
During the [[First Sacred War|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.
Some historians believe that [[Alexander the Great]] [[Alexander the Great#Death|died because of a hellebore overdose]], when he took it as medication.
==References and External links==
{{commonscat|Helleborus}}
*[http://rbg-web2.rbge.org.uk/cgi-bin/nph-readbtree.pl/feout?FAMILY_XREF=&GENUS_XREF=Helleborus&SPECIES_XREF=&TAXON_NAME_XREF=&RANK=species Flora Europaea: ''Helleborus'']
*[http://www.efloras.org/florataxon.aspx?flora_id=2&taxon_id=200008012 Flora of China: ''Helleborus'']
*Graham Rice & Elizabeth Strangman, ''The Gardener's Guide to Growing Hellebores'', David & Charles/Timber Press (1993) ISBN 0-7153-9973-X
*Brian Mathew, ''Hellebores'', Alpine Garden Society (1989) ISBN 0-900048-50-6
*Herrera, C. M. (2005). Post-floral perianth functionality: contribution of persistent sepals to seed development in ''Helleborus foetidus'' (Ranunculaceae). ''Amer. J. Bot.'' 92: 1486-1491 [http://www.amjbot.org/cgi/content/abstract/92/9/1486 abstract].
* [http://www.hellebore.com/ Garden writer Graham Rice's hellebore site]
* [http://www.hellebores.org Hellebores.org: A comprehensive online resource on the genus ''Helleborus'']
* [http://www.rhs.org.uk/learning/research/Sciencereport/Hellebore.pdf RHS plant pathology report on 'Hellebore Black Death' disease (pdf)]
* [http://phengels.club.fr/Cata
logueHelleborus.html A French hellebore enthusiast's non-commercial site]
==See also==
*[[Christmas flowers]]
[[Category:Ranunculaceae]]
[[Category:Witchcraft]]
[[Category:Abortifacients]]
[[Category:Christmas plants]]
[[Category:Garden plants]]
[[Category:Flowers]]
[[Category:Horticulture]]