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{{Short description|Section of a genus of flowering plants in the family Gesneriaceae}}
{{Redirect|African Violet|the 2019 film|African Violet (film)|the Blue Mitchell album|African Violet (album)}}
{{Use dmy dates|date=March 2018}}
{{Use dmy dates|date=March 2018}}
{{Automatic taxobox
{{Automatic taxobox
|image = Saintpaulia 'Pink Amiss' 02.jpg
| image = Saintpaulia ionantha.jpg
|image_caption = A ''Saintpaulia ionantha'' cultivar
| image_caption = ''[[Streptocarpus ionanthus]]'' in cultivation
|taxon = Saintpaulia
| taxon = Streptocarpus sect. Saintpaulia
|authority = [[Hermann Wendland|H.Wendl.]]
| authority = [[Hermann Wendland|H.Wendl.]]
|subdivision_ranks = Species
| subdivision_ranks = Species
|subdivision = {{center|
| subdivision = [[#Species|See text]].
''[[Saintpaulia goetzeana]]''<br/>
''[[Saintpaulia inconspicua]]''<br/>
''[[Saintpaulia ionantha]]''<br/>
''[[Saintpaulia pusilla]]''<br/>
''[[Saintpaulia shumensis]]''<br/>
''[[Saintpaulia teitensis]]''<br/>
''[[Saintpaulia tongwensis]]''}}
}}
}}
[[File:2007-04-20Saintpaulia ionantha03.jpg|thumb|''Streptocarpus'' ''ionanthus'' flowers]]
[[Image:Saintpaulia closeup.jpg|thumb|right|Saintpaulia flowers]]'''''Saintpaulia''''', commonly called '''African violet''', is a section within ''[[Streptocarpus]]'' subgenus ''Streptocarpella''<ref>{{Cite web|url=https://gesneriads.info/articles/saintpaulia/saintpaulia/taxonomy/greater-merger-current-taxonomic-status/|title=The Great Merger – Current Taxonomic Status {{!}} Gesneriad Reference Web|language=en-US|access-date=2020-03-11}}</ref>, consisting of 6–20 species of [[herbaceous]] [[perennial plant|perennial]] [[flowering plant]]s in the family [[Gesneriaceae]], native to [[Tanzania]] and adjacent southeastern [[Kenya]] in eastern tropical [[Africa]]. ''Saintpaulias'' are commonly indoor houseplants, but can also be kept as outdoor plants in certain climates.
'''''Streptocarpus'' sect. ''Saintpaulia''''' is a section within ''[[Streptocarpus]]'' subgenus ''Streptocarpella''<ref>{{Cite web|url=https://gesneriads.info/articles/saintpaulia/saintpaulia/taxonomy/greater-merger-current-taxonomic-status/|title=The Great Merger – Current Taxonomic Status {{!}} Gesneriad Reference Web|language=en-US|access-date=2020-03-11}}</ref> consisting of about ten species of [[herbaceous]] [[perennial plant|perennial]] [[flowering plant]]s in the family [[Gesneriaceae]], native to [[Tanzania]] and adjacent southeastern [[Kenya]] in eastern tropical [[Africa]]. The section was previously treated as a separate genus, ''Saintpaulia'', but [[Molecular phylogenetics|molecular phylogenetic]] studies showed that it was nested within the genus ''Streptocarpus''.


Although the common name for ''Saintpaulia'' is "African violet," they are completely unrelated to true [[Viola (plant)|violets]].
Species and [[cultivar]]s are commonly called '''African violets''' (although they are not closely related to true [[Viola (plant)|violets]]) or '''saintpaulias'''. They are commonly sold as house plants.


Several of the species and subspecies of ''Saintpaulia'' are [[endangered species|endangered]], and many more are threatened, due to their native [[cloud forest]] habitats being cleared for [[agriculture]]. The conservation status of '''''Saintpaulia ionantha''''' has been classed as [[near-threatened species|near-threatened]].
Several of the species and subspecies of the section are [[endangered species|endangered]], and many more are threatened, as their native [[cloud forest]] habitats are cleared for [[agriculture]]. The conservation status of ''[[Streptocarpus ionanthus]]'' has been classed as [[near-threatened species|near-threatened]].


== Description ==
== Description ==
{{expand section|plant structure|date=August 2013}}
{{expand section|plant structure|date=August 2013}}
Saintpaulias, which grow from 6-15 cm tall, can be anywhere from 6-30 cm wide. The [[leaves]] are rounded to oval, 2.5-8.5 cm long with a 2-10 cm [[Petiole (botany)|petiole]], finely [[trichome|hairy]], and have a fleshy texture. The [[flower]]s are 2-3 cm in diameter, with a five-lobed velvety corolla ("petals"), and grow in clusters of 3-10 or more on slender stalks called peduncles. Wild species can have violet, purple, pale blue, or white [[flowers]].<ref>MacDonald, Elvin "The World Book of House Plants" Popular Books</ref>


The plants get their common name "African violet" from their superficial resemblance to true [[Violet (plant)|violet]]s (''Viola'', family [[Violaceae]]).
Saintpaulia, which grow from 6–15&nbsp;cm tall, can be anywhere from 6–30&nbsp;cm wide. The [[leaves]] are rounded to oval, 2.5–8.5&nbsp;cm long with a 2–10&nbsp;cm [[Petiole (botany)|petiole]], finely [[trichome|hairy]], and have a fleshy texture. The [[flower]]s are 2–3&nbsp;cm in diameter, with a five-lobed velvety corolla ("petals"), and grow in clusters of 3–10 or more on slender stalks called peduncles. Wild species can have violet, purple, pale blue, or white [[flowers]].<ref>MacDonald, Elvin "The World Book of House Plants" Popular Books</ref>


===Sizes===
==Taxonomy==
This group of plants has lived in the biodiverse [[Eastern Arc Mountains|Eastern Arc]] [[Usambara Mountains]] in [[Tanga Province]] for millions of years. The name in the local Kisambaa language is Dughulushi. The Germans officially colonialized this area from about 1885, and shortly before this, Baron [[Walter von Saint Paul-Illaire]] (1860–1940) was made district commissioner of [[Tanga Province|Tanga province]], [[German East Africa|Tanganyika]] (now [[Tanzania]]) in Africa. He used to enjoy walking in the rainforest and they reminded him of the violets back home. He called them Usambaraveilchen (Usambara violets). In 1892 he sent seeds back to his father, who gave them to an amateur botanist, [[Hermann Wendland]], in [[Germany]]. Wendland scientifically described the genus ''Saintpaulia'', and original species ''S. ionantha'' in 1893,<ref>Smithsonian World Checklist of the Gesneriaceae</ref> naming the genus for Saint Paul-Illaire and his father.<ref>Burkhardt, Lotte. Verzeichnis eponymischer Pflanzennamen. Erweiterte Edition. 2018.</ref> Two British plant enthusiasts, Sir John Kirk and the Reverend W.E. Taylor, had earlier collected and submitted specimens to the [[Royal Botanic Gardens, Kew]], in 1884 and 1887 respectively, but the quality of specimens was insufficient to permit scientific description at that time.
Plants can be classified as one of several sizes based on its above-ground diameter. Although the size per category is not set in stone, these are a general guideline.<ref>{{cite web|title=Grow-African-Violets.com|url=http://www.grow-african-violets.com/african-violet-plant-size.html|accessdate=30 May 2013}}</ref><ref>{{cite web|title=The Violet Barn|url=http://www.robsviolet.com/african_violets.htm|accessdate=30 May 2013}}</ref>
* Micro: less than 3 inches
* Super-mini: 3 to 4 inches
* Mini: between 4 and 6 inches
* Semi-mini: between 6 and 8-10 inches
* Standard: between 8-10 to 12-16 inches
* Large/Giant: over 12-16 inches


Revisions of the genus by [[Brian Laurence Burtt|B.L. Burtt]] expanded the genus to approximately 20 species. Following studies which showed most of the species to be very poorly differentiated, both [[genetically]] and [[morphology (biology)|morphologically]], the number of species was reduced to six in a 2006 treatment, with the majority of former species reduced to subspecies under ''S. ionantha''.<ref>Darbyshire (2006) ''Saintpaulia'', pp. 50-72, in Beentjy & Ghazanfar (eds), Fl. Trop. East Africa</ref> In 2009, 9 [[species]], 8 [[subspecies]], and 2 varieties were recognized.<ref>Pilon F (2012) ''Saintpaulia''. The history and origin of the African Violet.</ref>
== Growth ==
{{expand section|nodes and internodes, adventitious roots, growing from seed, crown|date=August 2013}}


A [[Molecular phylogenetics|molecular phylogenetic]] study in 2015 confirmed previous studies showing that species placed in ''Saintpaulia'' were deeply embedded within the genus ''Streptocarpus'',<ref name=NishHughBrigHast15/> supporting the transfer of all ''Saintpaulia'' species to ''Streptocarpus'' in 2012.<ref name=Chri12/> Former ''Saintpaulia'' species did form a [[Monophyly|monophyletic group]], and were placed in section ''Saintpaulia'' of ''Streptocarpus'' subgenus ''Streptocarpella''.<ref name=NishHughBrigHast15/>
=== Temperature ===
Saintpaulias are highly sensitive to temperature changes, especially rapid leaf cooling. Spilling cold water on African violet leaves causes discoloration. This is thought to be because rapid leaf cooling causes [[cell vacuole]] collapse in the [[palisade mesophyll]] cells.<ref name="Plos—Vacuole collapse">{{cite journal|last=Kadohama|first=Noriaki|author2=Tatsuaki Goh |author3=Miwa Ohnishi |author4=Hidehiro Fukaki |author5=Tetsuro Mimura |author6=Yoshihiro Suzuki |title=Sudden Collapse of Vacuoles in Saintpaulia sp. Palisade Cells Induced by a Rapid Temperature Decrease|journal=PLOS ONE|date=February 2013|volume=8|issue=2|doi=10.1371/journal.pone.0057259|url=http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0057259 |pages=e57259 |pmid=23451194 |pmc=3581458}}</ref>


=== Propagation ===
===Species===
All the species previously placed in the genus ''Saintpaulia'' are now placed in ''Streptocarpus'' section ''Saintpaulia''. Ten species were recognized, {{As of|2020|March|lc=yes}}.<ref name=NishHughBrigHast15/><ref name=POWO_Saintpaulia/>
African violets are commonly [[Plant propagation|propagated]] [[asexual reproduction|asexually]]. Plants can be divided into smaller daughter plants or even grown from leaf cuttings.<ref name="Growing African violets">{{cite web|last=Thomas|first=Paul A|title=Growing African Violets|url=http://www.caes.uga.edu/publications/pubDetail.cfm?pk_ID=6342|publisher=CAES Publications|accessdate=11 August 2013}}</ref>
{{Div col|colwidth=24em}}
Growing African violets from [[seed]] is rare and most commercially available plants are produced from cuttings and [[tissue culture]].<ref name="Commercial culture of Saintpaulia" />
* ''[[Streptocarpus afroviola]]'' <small>Christenh.</small>
* ''[[Streptocarpus albus]]'' <small>(E.A.Bruce) I.Darbysh.</small>
* ''[[Streptocarpus brevipilosus]]'' <small>(B.L.Burtt) Mich.Möller & Haston</small>
* ''[[Streptocarpus goetzeanus]]'' <small>(Engl.) Christenh.</small>
* ''[[Streptocarpus inconspicuus]]'' <small>(B.L.Burtt) Christenh.</small>
* ''[[Streptocarpus ionanthus]]'' <small>(H.Wendl.) Christenh.</small>
* ''[[Streptocarpus nitidus]]'' <small>(B.L.Burtt) Mich.Möller & Haston</small>
* ''[[Streptocarpus shumensis]]'' <small>(B.L.Burtt) Christenh.</small>
* ''[[Streptocarpus teitensis]]'' <small>(B.L.Burtt) Christenh.</small>
* ''[[Streptocarpus ulugurensis]]'' <small>(Haston) Haston</small>
{{Div col end}}


Formerly recognized ''Saintpaulia'' species and infraspecies are listed below with their accepted name in ''Streptocarpus''.<ref name="POWO_Saintpaulia">{{citation |mode=cs1 |title=Search for ''Saintpaulia'' |work=[[Plants of the World Online]] |publisher=Royal Botanic Gardens, Kew |url=https://powo.science.kew.org/results?q=Saintpaulia |access-date=2020-03-11 }}</ref>
=== Flowering ===
{{Div col|colwidth=36em}}
The African violet is a [[Photoperiodism|day-neutral plant]] regarding flower development.<ref>Modeling Inflorescence Development of the African Violet (Saintpaulia ionantha Wendl.). James E. Faust and Royal D. Heins, J. AMER. SOC. HORT. SCI. 119(4):727–734. 1994.</ref><ref>Saintpaulia ionantha, Stromme E, 1985, p. 48–49. In: A. Halevy (ed.). CRC handbook of flowering. vol. 3. CRC Press, Boca Raton, Fla.</ref>
*''Saintpaulia alba'' <small>E.A.Bruce</small> = ''[[Streptocarpus albus]]'' <small>(E.A.Bruce) I.Darbysh.</small>
*''Saintpaulia amaniensis'' <small>E.P.Roberts</small> = ''[[Streptocarpus ionanthus]]'' subsp. ''grotei'' <small>(Engl.) Christenh.</small>
*''Saintpaulia brevipilosa'' <small>B.L.Burtt</small> = ''[[Streptocarpus brevipilosus]]'' <small>(B.L.Burtt) Mich.Möller & Haston</small>
*''Saintpaulia confusa'' <small>B.L.Burtt</small> = ''[[Streptocarpus ionanthus]]'' subsp. ''grotei'' <small>(Engl.) Christenh.</small>
*''Saintpaulia difficilis'' <small>B.L.Burtt</small> = ''[[Streptocarpus ionanthus]]'' subsp. ''grotei'' <small>(Engl.) Christenh.</small>
*''Saintpaulia diplotricha'' <small>B.L.Burtt</small> = ''[[Streptocarpus ionanthus]]'' var. ''diplotrichus'' <small>(B.L.Burtt) Christenh.</small>
*''Saintpaulia goetzeana'' <small>Engl.</small> = ''[[Streptocarpus goetzeanus]]'' <small>(Engl.) Christenh.</small>
*''Saintpaulia grandifolia'' <small>B.L.Burtt</small> = ''[[Streptocarpus ionanthus]]'' subsp. ''grandifolius'' <small>(B.L.Burtt) Christenh.</small>
*''Saintpaulia grotei'' <small>Engl.</small> = ''[[Streptocarpus]] ionanthus'' subsp. ''grotei'' <small>(Engl.) Christenh.</small>
*''Saintpaulia inconspicua'' <small>B.L.Burtt</small> = ''[[Streptocarpus inconspicuus]]'' <small>(B.L.Burtt) Christenh.</small>
*''Saintpaulia intermedia'' <small>B.L.Burtt</small> = ''[[Streptocarpus ionanthus]]'' subsp. ''pendulus'' <small>(B.L.Burtt) Christenh.</small>
*''Saintpaulia ionantha'' <small>H.Wendl.</small> = ''[[Streptocarpus ionanthus]]'' <small>(H.Wendl.) Christenh.</small>
**''Saintpaulia ionantha'' subsp. ''grandifolia'' <small>(B.L.Burtt) I.Darbysh.</small> = ''Streptocarpus ionanthus'' subsp. ''grandifolius'' <small>(B.L.Burtt) Christenh.</small>
**''Saintpaulia ionantha'' subsp. ''grotei'' <small>(Engl.) I.Darbysh.</small> = ''Streptocarpus ionanthus'' subsp. ''grotei'' <small>(Engl.) Christenh.</small>
**''Saintpaulia ionantha'' subsp. ''mafiensis'' <small>I.Darbysh. & Pócs</small> = ''Streptocarpus ionanthus'' subsp. ''mafiensis'' <small>(I.Darbysh. & Pócs) Christenh.</small>
**''Saintpaulia ionantha'' subsp. ''nitida'' <small>(B.L.Burtt) I.Darbysh.</small> = ''[[Streptocarpus nitidus]]'' <small>(B.L.Burtt) Mich.Möller & Haston</small>
**''Saintpaulia ionantha'' subsp. ''occidentalis'' <small>(B.L.Burtt) I.Darbysh.</small> = ''Streptocarpus ionanthus'' subsp. ''occidentalis'' <small>(B.L.Burtt) Christenh.</small>
**''Saintpaulia ionantha'' subsp. ''orbicularis'' <small>(B.L.Burtt) I.Darbysh.</small> = ''Streptocarpus ionanthus'' subsp. ''orbicularis'' <small>(B.L.Burtt) Christenh.</small>
**''Saintpaulia ionantha'' subsp. ''pendula'' <small>(B.L.Burtt) I.Darbysh.</small> = ''Streptocarpus ionanthus'' subsp. ''pendulus'' <small>(B.L.Burtt) Christenh.</small>
**''Saintpaulia ionantha'' subsp. ''rupicola'' <small>(B.L.Burtt) I.Darbysh..</small> = ''Streptocarpus ionanthus'' subsp. ''rupicola'' <small>(B.L.Burtt) Christenh.</small>
**''Saintpaulia ionantha'' subsp. ''velutina'' <small>(B.L.Burtt) I.Darbysh.</small> = ''Streptocarpus ionanthus'' subsp. ''velutinus'' <small>(B.L.Burtt) Christenh.</small>
**''Saintpaulia ionantha'' var. ''diplotricha'' <small>(B.L.Burtt) I.Darbysh.</small> = ''Streptocarpus ionanthus'' var. ''diplotrichus'' <small>(B.L.Burtt) Christenh.</small>
*''Saintpaulia kewensis'' <small>C.B.Clarke</small> = ''[[Streptocarpus ionanthus]]'' <small>(H.Wendl.) Christenh.</small>
*''Saintpaulia magungensis'' <small>E.P.Roberts</small> = ''[[Streptocarpus ionanthus]]'' subsp. ''grotei'' <small>(Engl.) Christenh.</small>
**''Saintpaulia magungensis'' var. ''occidentalis'' <small>B.L.Burtt</small> = ''Streptocarpus ionanthus'' subsp. ''occidentalis'' <small>(B.L.Burtt) Christenh.</small>
*''Saintpaulia nitida'' <small>B.L.Burtt</small> = ''[[Streptocarpus nitidus]]'' <small>(B.L.Burtt) Mich.Möller & Haston</small>
*''Saintpaulia orbicularis'' <small>B.L.Burtt</small> = ''[[Streptocarpus ionanthus]]'' subsp. ''orbicularis'' <small>(B.L.Burtt) Christenh.</small>
*''Saintpaulia pendula'' <small>B.L.Burtt</small> = ''[[Streptocarpus ionanthus]]'' subsp. ''pendulus'' <small>(B.L.Burtt) Christenh.</small>
*''Saintpaulia pusilla'' <small>Engl.</small> = ''[[Streptocarpus afroviola]]'' <small>Christenh.</small>
*''Saintpaulia rupicola'' <small>B.L.Burtt</small> = ''[[Streptocarpus ionanthus]]'' subsp. ''rupicola'' <small>(B.L.Burtt) Christenh.</small>
*''Saintpaulia shumensis'' <small>B.L.Burtt</small> = ''[[Streptocarpus shumensis]]'' <small>(B.L.Burtt) Christenh.</small>
*''Saintpaulia teitensis'' <small>B.L.Burtt</small> = ''[[Streptocarpus teitensis]]'' <small>(B.L.Burtt) Christenh.</small>
*''Saintpaulia tongwensis'' <small>B.L.Burtt</small> = ''[[Streptocarpus ionanthus]]'' <small>(H.Wendl.) Christenh.</small>
*''Saintpaulia ulugurensis'' <small>Haston</small> = ''[[Streptocarpus ulugurensis]]'' <small>(Haston) Haston</small>
*''Saintpaulia velutina'' <small>B.L.Burtt</small> = ''[[Streptocarpus ionanthus]]'' subsp. ''velutinus'' <small>(B.L.Burtt) Christenh.</small>
*''Saintpaulia watkinsii'' <small>Haston</small> = ''[[Streptocarpus afroviola]]'' var. ''watkinsii'' <small>(Haston) Christenh.</small>
{{Div col end}}


== Distribution ==
== Distribution ==
Saintpaulias are native to eastern tropical [[Africa]]. There is a concentration of species in the [[Nguru mountains]] of [[Tanzania]].
Saintpaulias are native to eastern tropical [[Africa]]. There is a concentration of species in the [[Nguru mountains]] of [[Tanzania]].


==Taxonomy==
==Cultivation==
[[File:Saintpaulia 'Pink Amiss' 02.jpg|thumb|Cultivar 'Pink Amiss']]
The plants get their common name "African violet" from their superficial resemblance to true [[Violet (plant)|violet]]s (''Viola'', family [[Violaceae]]).
[[File:Saintpaulia 'Red Velvet' 02.jpg|thumb|Cultivar 'Red Velvet']]
Saintpaulias are widely cultivated as [[house plant]]s. Until recently, only a few of the ten or so species that exist have been used in breeding programs for the hybrids available in the market; most of the [[cultivar]]s available as house plants are derived from ''[[Streptocarpus ionanthus]]'' (syn. ''S. kewensis''). A wider range of species is now being looked at as sources of genes to introduce into modern cultivars.


The [[African Violet Society of America]] is the [[International Cultivar Registration Authority]] for the section and its cultivars.
The genus is named after Baron [[Walter von Saint Paul-Illaire]] (1860–1940), the district commissioner of [[Tanga Province|Tanga]] province who discovered the plant in [[German East Africa|Tanganyika]] (now [[Tanzania]]) in Africa in 1892 and sent seeds back to his father, an amateur botanist in [[Germany]], and for the father.<ref>Burkhardt, Lotte. Verzeichnis eponymischer Pflanzennamen. Erweiterte Edition. 2018.</ref> Two British plant enthusiasts, Sir John Kirk and the Reverend W.E. Taylor, had earlier collected and submitted specimens to the [[Royal Botanic Gardens, Kew]], in 1884 and 1887 respectively, but the quality of specimens was insufficient to permit scientific description at that time. The genus ''Saintpaulia'', and original species ''S. ionantha'', were scientifically described by [[Hermann Wendland|H. Wendland]] in 1893.<ref>Smithsonian World Checklist of the Gesneriaceae</ref>


===Sizes===
Revisions of the genus by [[Brian Laurence Burtt|B.L. Burtt]] expanded the genus to approximately 20 species. Due to recent studies which showed most of the species to be very poorly differentiated, both [[genetically]] and [[morphology (biology)|morphologically]], the number of species has been reduced to six, with the majority of former species reduced to subspecies under ''S. ionantha'', in a recent floristic treatment.<ref>Darbyshire (2006) Saintpaulia, pp. 50-72, in Beentjy & Ghazanfar (eds), Fl. Trop. East Africa</ref> As of 2009, 9 [[species]], 8 [[subspecies]], and 2 varieties have been recognized.<ref>Pilon F (2012) Saintpaulia. The history and origin of the African Violet.</ref>
Plants can be classified as one of several sizes based on their above-ground diameter. The size per category is not rigid, but a general guideline.<ref>{{cite web|title=Grow-African-Violets.com|url=http://www.grow-african-violets.com/african-violet-plant-size.html|access-date=30 May 2013}}</ref><ref>{{cite web|title=The Violet Barn|url=http://www.robsviolet.com/african_violets.htm|access-date=30 May 2013}}</ref>
* Micro: less than 3 inches
* Super-mini: 3 to 4 inches[[File:African violet (Saintpaulia).jpg|thumb|A [[Variegation|variegated]] and [[double-flowered]] cultivar]]
* Mini: between 4 and 6 inches
* Semi-mini: between 6 and 8–10 inches
* Standard: between 8–10 and 12–16 inches
* Large/Giant: over 12–16 inches


=== Temperature ===
'''Old name vs. current name'''
Saintpaulias are highly sensitive to temperature changes, especially rapid leaf cooling. Spilling cold water on African violet leaves causes discoloration. This is thought to be because rapid leaf cooling causes [[cell vacuole]] collapse in the [[palisade mesophyll]] cells.<ref name="Plos—Vacuole collapse">{{cite journal|last=Kadohama|first=Noriaki|author2=Tatsuaki Goh |author3=Miwa Ohnishi |author4=Hidehiro Fukaki |author5=Tetsuro Mimura |author6=Yoshihiro Suzuki |title=Sudden Collapse of Vacuoles in Saintpaulia sp. Palisade Cells Induced by a Rapid Temperature Decrease|journal=PLOS ONE|date=February 2013|volume=8|issue=2|doi=10.1371/journal.pone.0057259|pages=e57259 |pmid=23451194 |pmc=3581458|doi-access=free}}</ref>


=== Propagation ===
* ''Saintpaulia amaniensis'' = ''S. ionantha'' ssp. ''grotei''
African violets are commonly [[Plant propagation|propagated]] [[asexual reproduction|asexually]]. Plants can be divided into smaller daughter plants or even grown from leaf cuttings.<ref name="Growing African violets">{{cite web|last=Thomas|first=Paul A|title=Growing African Violets|url=http://www.caes.uga.edu/publications/pubDetail.cfm?pk_ID=6342|publisher=CAES Publications|access-date=11 August 2013}}</ref>
* ''Saintpaulia brevipilosa'' = ''S. ionantha'' ssp. ''velutina''
Growing African violets from [[seed]] is rare, and most commercially available plants are produced from cuttings and [[tissue culture]].<ref name="Commercial culture of Saintpaulia" />
* ''Saintpaulia confusa'' = ''S. ionantha'' ssp. ''grotei''
* ''Saintpaulia difficilis'' = ''S. ionantha'' ssp. ''grotei''
* ''Saintpaulia diplotricha'' = ''S. ionantha'' ssp. ''ionantha'' var. ''diplotricha''
* ''Saintpaulia grandifolia'' = ''S. ionantha'' ssp. ''grandifolia''
* ''Saintpaulia grotei'' = ''S. ionantha'' ssp. ''grotei''
* ''Saintpaulia intermedia'' = ''S. ionantha'' ssp. ''pendula''
* ''Saintpaulia magungensis'' = ''S. ionantha'' ssp. ''grotei''
* ''Saintpaulia magungensis'' var. ''minima'' = ''S. ionantha'' ssp. ''grotei''
* ''Saintpaulia magungensis'' var. ''occidentalis'' = ''S. ionantha'' ssp. ''occidentalis''
* ''Saintpaulia nitida'' = ''S. ionantha'' ssp. ''nitida''
* ''Saintpaulia orbicularis'' = ''S. ionantha'' ssp. ''orbicularis''
* ''Saintpaulia pendula'' = ''S. ionantha'' ssp. ''pendula''
* ''Saintpaulia pendula'' var. ''kizarae'' = ''S. ionantha'' ssp. ''pendula''
* ''Saintpaulia rupicola'' = ''S. ionantha'' ssp. ''rupicola''
* ''Saintpaulia tongwensis'' = ''S. ionantha'' ssp. ''ionantha'' var. ''ionantha''
* ''Saintpaulia velutina'' = ''S. ionantha'' ssp. ''velutina''


=== Flowering ===
The genus is most closely related to ''[[Streptocarpus]]'', with recent phylogenetic studies suggesting it has evolved directly from subgenus ''Streptocarpella''.
The African violet is a [[Photoperiodism|day-neutral plant]] regarding flower development.<ref>Modeling Inflorescence Development of the African Violet (Saintpaulia ionantha Wendl.). James E. Faust and Royal D. Heins, J. AMER. SOC. HORT. SCI. 119(4):727–734. 1994.</ref><ref>Saintpaulia ionantha, Stromme E, 1985, p. 48–49. In: A. Halevy (ed.). CRC handbook of flowering. vol. 3. CRC Press, Boca Raton, Fla.</ref>


==Cultivation==
==In culture==
African violets have become a traditional gift in the [[developed world]]. They are often offered for sale at holidays.<ref name="Commercial culture of Saintpaulia">{{cite web|last=Chen|first=J|title=Cultural Guidelines for Commercial Production of African Violets (Saintpaulia ionantha)|url=http://edis.ifas.ufl.edu/ep360|publisher=University of Florida|access-date=13 August 2013}}</ref>
<!-- Deleted image removed: [[Image:Pink African Violet.jpg|thumb|left|A pink, [[double-flowered]] cultivar|{{deletable image-caption|1=Thursday, 2 July 2009}}]] -->
Saintpaulias are widely cultivated as [[house plant]]s. Until recently, only a few of these species have been used in breeding programs for the hybrids available in the market; most available as house plants are [[cultivar]]s derived from ''Saintpaulia ionantha'' (syn. ''S. kewensis''). A wider range of species is now being looked at as sources of genes to introduce into modern cultivars.


They are a popular house plant in many countries, as they can flower during most of the year and are fairly durable to neglect.<ref>{{Cite news |last=Honan |first=William H. |date=1999-05-26 |title=Lyndon Lyon Is Dead at 94; A Breeder of African Violets |language=en-US |work=The New York Times |url=https://www.nytimes.com/1999/05/26/nyregion/lyndon-lyon-is-dead-at-94-a-breeder-of-african-violets.html |access-date=2022-04-15 |issn=0362-4331}}</ref><ref>{{Cite web |title=African Violets: Why So Popular? {{!}} Gesneriad Reference Web |url=https://gesneriads.info/articles/saintpaulia/saintpaulia/history-in-cultivation/african-violets-popular/ |access-date=2022-04-16 |language=en-US}}</ref>
The [[African Violet Society of America]] is the [[International Cultivar Registration Authority]] for the genus ''Saintpaulia'' and its cultivars.


In the 1997 film ''[[Amistad (film)|Amistad]]'', ex-president [[John Quincy Adams]] shows the lead slave [[Joseph Cinqué]] his flower collection which contains an African violet which Cinque then recognises from his home land.{{citation needed|date=June 2024}}
==In culture==
African violets have long been associated with mothers and motherhood. For this reason they have been a traditional gift to mothers in many cultures around the world. African violets are also associated with [[Easter]] and [[Valentine's Day]].<ref name="Commercial culture of Saintpaulia">{{cite web|last=Chen|first=J|title=Cultural Guidelines for Commercial Production of African Violets (Saintpaulia ionantha)|url=http://edis.ifas.ufl.edu/ep360|publisher=University of Florida|accessdate=13 August 2013}}</ref>


==References==
==References==
{{Reflist}}
{{Reflist|refs=
<ref name=Chri12>{{Citation |mode=cs1 |last1=Christenhusz |first1=Maarten J.M. |date=2012 |title=On African violets and Cape primroses—towards a monophyletic ''Streptocarpus'' (Gesneriaceae) |journal=Phytotaxa |volume=46 |pages=3–9 |url=https://www.researchgate.net/publication/285527411 |access-date=2020-03-12 |doi=10.11646/phytotaxa.46.1.2 }}</ref>

<ref name=NishHughBrigHast15>{{Citation |mode=cs1 |last1=Nishii |first1=Kanae |last2=Hughes |first2=Mark |last3=Briggs |first3=Marie |last4=Haston |first4=Elspeth |last5=Christie |first5=Frieda |last6=DeVilliers |first6=Margaret J. |last7=Hanekom |first7=Thea |last8=Roos |first8=Wiets G. |last9=Bellstedt |first9=Dirk U. |last10=Möller |first10=Michael |date=2015 |title=''Streptocarpus'' redefined to include all Afro-Malagasy Gesneriaceae: Molecular phylogenies prove congruent with geographical distribution and basic chromosome numbers and uncover remarkable morphological homoplasies |journal=Taxon |volume=64 |issue=6 |pages=1243–1274 |url=https://gesneriads.info/wp-content/uploads/2019/02/1243_1274_Nishii-downsized.pdf |access-date=2020-03-12 |doi=10.12705/646.8 |name-list-style=amp }}</ref>
}}


==External links==
==External links==
*{{Commonscatinline}}
{{Commons category|position=left}}
*{{Wikispeciesinline}}
{{Wikispecies}}
*[http://www.avsa.org African Violet Society of America website]
*[http://www.avsa.org African Violet Society of America website]
*[https://web.archive.org/web/20070818042857/http://www.violeteafricane.ro/ African Violet in Romania - Pasionata de violete africane]
*[http://avsc.ca African Violet Society of Canada website]
*[http://avsc.ca African Violet Society of Canada website]
*[http://www.saintpauliasallskapet.se Swedish African Violet Society website]
*[https://web.archive.org/web/20061002074753/http://www.gesneriads.ca/saintart.htm Gesneriad Reference Web Saintpaulia article]
*[https://web.archive.org/web/20061002074753/http://www.gesneriads.ca/saintart.htm Gesneriad Reference Web Saintpaulia article]
*[http://www.african-violet.de/ African Violet in Germany]
*[http://www.africanviolet.in.th/ African Violet Thailand]
*[http://www.babyviolets.com Baby Violets - African Violet Houseplants]
*[http://www.babyviolets.com Baby Violets - African Violet Houseplants]


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[[Category:Flora of East Tropical Africa]]
[[Category:Flora of East Tropical Africa]]
[[Category:Garden plants of Africa]]
[[Category:Garden plants of Africa]]
[[Category:Gesneriaceae genera]]
[[Category:House plants]]
[[Category:House plants]]
[[Category:Saintpaulia| ]]
[[Category:Streptocarpus| ]]
[[Category:Plant sections]]
[[Category:Flora of the Eastern Arc forests]]

Latest revision as of 22:07, 18 December 2024

"African Violet" redirects here. For the 2019 film, see African Violet (film). For the Blue Mitchell album, see African Violet (album).

Streptocarpus sect. Saintpaulia
Streptocarpus ionanthus in cultivation
Scientific classification Edit this classification
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Eudicots
Clade: Asterids
Order: Lamiales
Family: Gesneriaceae
Genus: Streptocarpus
Subgenus: S. subg. Streptocarpella
Section: S. sect. Saintpaulia
H.Wendl.
Species

See text.

Streptocarpus ionanthus flowers

Streptocarpus sect. Saintpaulia is a section within Streptocarpus subgenus Streptocarpella[1] consisting of about ten species of herbaceous perennial flowering plants in the family Gesneriaceae, native to Tanzania and adjacent southeastern Kenya in eastern tropical Africa. The section was previously treated as a separate genus, Saintpaulia, but molecular phylogenetic studies showed that it was nested within the genus Streptocarpus.

Species and cultivars are commonly called African violets (although they are not closely related to true violets) or saintpaulias. They are commonly sold as house plants.

Several of the species and subspecies of the section are endangered, and many more are threatened, as their native cloud forest habitats are cleared for agriculture. The conservation status of Streptocarpus ionanthus has been classed as near-threatened.

Description

[edit]

Saintpaulias, which grow from 6-15 cm tall, can be anywhere from 6-30 cm wide. The leaves are rounded to oval, 2.5-8.5 cm long with a 2-10 cm petiole, finely hairy, and have a fleshy texture. The flowers are 2-3 cm in diameter, with a five-lobed velvety corolla ("petals"), and grow in clusters of 3-10 or more on slender stalks called peduncles. Wild species can have violet, purple, pale blue, or white flowers.[2]

The plants get their common name "African violet" from their superficial resemblance to true violets (Viola, family Violaceae).

Taxonomy

[edit]

This group of plants has lived in the biodiverse Eastern Arc Usambara Mountains in Tanga Province for millions of years. The name in the local Kisambaa language is Dughulushi. The Germans officially colonialized this area from about 1885, and shortly before this, Baron Walter von Saint Paul-Illaire (1860–1940) was made district commissioner of Tanga province, Tanganyika (now Tanzania) in Africa. He used to enjoy walking in the rainforest and they reminded him of the violets back home. He called them Usambaraveilchen (Usambara violets). In 1892 he sent seeds back to his father, who gave them to an amateur botanist, Hermann Wendland, in Germany. Wendland scientifically described the genus Saintpaulia, and original species S. ionantha in 1893,[3] naming the genus for Saint Paul-Illaire and his father.[4] Two British plant enthusiasts, Sir John Kirk and the Reverend W.E. Taylor, had earlier collected and submitted specimens to the Royal Botanic Gardens, Kew, in 1884 and 1887 respectively, but the quality of specimens was insufficient to permit scientific description at that time.

Revisions of the genus by B.L. Burtt expanded the genus to approximately 20 species. Following studies which showed most of the species to be very poorly differentiated, both genetically and morphologically, the number of species was reduced to six in a 2006 treatment, with the majority of former species reduced to subspecies under S. ionantha.[5] In 2009, 9 species, 8 subspecies, and 2 varieties were recognized.[6]

A molecular phylogenetic study in 2015 confirmed previous studies showing that species placed in Saintpaulia were deeply embedded within the genus Streptocarpus,[7] supporting the transfer of all Saintpaulia species to Streptocarpus in 2012.[8] Former Saintpaulia species did form a monophyletic group, and were placed in section Saintpaulia of Streptocarpus subgenus Streptocarpella.[7]

Species

[edit]

All the species previously placed in the genus Saintpaulia are now placed in Streptocarpus section Saintpaulia. Ten species were recognized, as of March 2020.[7][9]

Formerly recognized Saintpaulia species and infraspecies are listed below with their accepted name in Streptocarpus.[9]

  • Saintpaulia alba E.A.Bruce = Streptocarpus albus (E.A.Bruce) I.Darbysh.
  • Saintpaulia amaniensis E.P.Roberts = Streptocarpus ionanthus subsp. grotei (Engl.) Christenh.
  • Saintpaulia brevipilosa B.L.Burtt = Streptocarpus brevipilosus (B.L.Burtt) Mich.Möller & Haston
  • Saintpaulia confusa B.L.Burtt = Streptocarpus ionanthus subsp. grotei (Engl.) Christenh.
  • Saintpaulia difficilis B.L.Burtt = Streptocarpus ionanthus subsp. grotei (Engl.) Christenh.
  • Saintpaulia diplotricha B.L.Burtt = Streptocarpus ionanthus var. diplotrichus (B.L.Burtt) Christenh.
  • Saintpaulia goetzeana Engl. = Streptocarpus goetzeanus (Engl.) Christenh.
  • Saintpaulia grandifolia B.L.Burtt = Streptocarpus ionanthus subsp. grandifolius (B.L.Burtt) Christenh.
  • Saintpaulia grotei Engl. = Streptocarpus ionanthus subsp. grotei (Engl.) Christenh.
  • Saintpaulia inconspicua B.L.Burtt = Streptocarpus inconspicuus (B.L.Burtt) Christenh.
  • Saintpaulia intermedia B.L.Burtt = Streptocarpus ionanthus subsp. pendulus (B.L.Burtt) Christenh.
  • Saintpaulia ionantha H.Wendl. = Streptocarpus ionanthus (H.Wendl.) Christenh.
    • Saintpaulia ionantha subsp. grandifolia (B.L.Burtt) I.Darbysh. = Streptocarpus ionanthus subsp. grandifolius (B.L.Burtt) Christenh.
    • Saintpaulia ionantha subsp. grotei (Engl.) I.Darbysh. = Streptocarpus ionanthus subsp. grotei (Engl.) Christenh.
    • Saintpaulia ionantha subsp. mafiensis I.Darbysh. & Pócs = Streptocarpus ionanthus subsp. mafiensis (I.Darbysh. & Pócs) Christenh.
    • Saintpaulia ionantha subsp. nitida (B.L.Burtt) I.Darbysh. = Streptocarpus nitidus (B.L.Burtt) Mich.Möller & Haston
    • Saintpaulia ionantha subsp. occidentalis (B.L.Burtt) I.Darbysh. = Streptocarpus ionanthus subsp. occidentalis (B.L.Burtt) Christenh.
    • Saintpaulia ionantha subsp. orbicularis (B.L.Burtt) I.Darbysh. = Streptocarpus ionanthus subsp. orbicularis (B.L.Burtt) Christenh.
    • Saintpaulia ionantha subsp. pendula (B.L.Burtt) I.Darbysh. = Streptocarpus ionanthus subsp. pendulus (B.L.Burtt) Christenh.
    • Saintpaulia ionantha subsp. rupicola (B.L.Burtt) I.Darbysh.. = Streptocarpus ionanthus subsp. rupicola (B.L.Burtt) Christenh.
    • Saintpaulia ionantha subsp. velutina (B.L.Burtt) I.Darbysh. = Streptocarpus ionanthus subsp. velutinus (B.L.Burtt) Christenh.
    • Saintpaulia ionantha var. diplotricha (B.L.Burtt) I.Darbysh. = Streptocarpus ionanthus var. diplotrichus (B.L.Burtt) Christenh.
  • Saintpaulia kewensis C.B.Clarke = Streptocarpus ionanthus (H.Wendl.) Christenh.
  • Saintpaulia magungensis E.P.Roberts = Streptocarpus ionanthus subsp. grotei (Engl.) Christenh.
    • Saintpaulia magungensis var. occidentalis B.L.Burtt = Streptocarpus ionanthus subsp. occidentalis (B.L.Burtt) Christenh.
  • Saintpaulia nitida B.L.Burtt = Streptocarpus nitidus (B.L.Burtt) Mich.Möller & Haston
  • Saintpaulia orbicularis B.L.Burtt = Streptocarpus ionanthus subsp. orbicularis (B.L.Burtt) Christenh.
  • Saintpaulia pendula B.L.Burtt = Streptocarpus ionanthus subsp. pendulus (B.L.Burtt) Christenh.
  • Saintpaulia pusilla Engl. = Streptocarpus afroviola Christenh.
  • Saintpaulia rupicola B.L.Burtt = Streptocarpus ionanthus subsp. rupicola (B.L.Burtt) Christenh.
  • Saintpaulia shumensis B.L.Burtt = Streptocarpus shumensis (B.L.Burtt) Christenh.
  • Saintpaulia teitensis B.L.Burtt = Streptocarpus teitensis (B.L.Burtt) Christenh.
  • Saintpaulia tongwensis B.L.Burtt = Streptocarpus ionanthus (H.Wendl.) Christenh.
  • Saintpaulia ulugurensis Haston = Streptocarpus ulugurensis (Haston) Haston
  • Saintpaulia velutina B.L.Burtt = Streptocarpus ionanthus subsp. velutinus (B.L.Burtt) Christenh.
  • Saintpaulia watkinsii Haston = Streptocarpus afroviola var. watkinsii (Haston) Christenh.

Distribution

[edit]

Saintpaulias are native to eastern tropical Africa. There is a concentration of species in the Nguru mountains of Tanzania.

Cultivation

[edit]
Cultivar 'Pink Amiss'
Cultivar 'Red Velvet'

Saintpaulias are widely cultivated as house plants. Until recently, only a few of the ten or so species that exist have been used in breeding programs for the hybrids available in the market; most of the cultivars available as house plants are derived from Streptocarpus ionanthus (syn. S. kewensis). A wider range of species is now being looked at as sources of genes to introduce into modern cultivars.

The African Violet Society of America is the International Cultivar Registration Authority for the section and its cultivars.

Sizes

[edit]

Plants can be classified as one of several sizes based on their above-ground diameter. The size per category is not rigid, but a general guideline.[10][11]

  • Micro: less than 3 inches
  • Super-mini: 3 to 4 inches
    A variegated and double-flowered cultivar
  • Mini: between 4 and 6 inches
  • Semi-mini: between 6 and 8–10 inches
  • Standard: between 8–10 and 12–16 inches
  • Large/Giant: over 12–16 inches

Temperature

[edit]

Saintpaulias are highly sensitive to temperature changes, especially rapid leaf cooling. Spilling cold water on African violet leaves causes discoloration. This is thought to be because rapid leaf cooling causes cell vacuole collapse in the palisade mesophyll cells.[12]

Propagation

[edit]

African violets are commonly propagated asexually. Plants can be divided into smaller daughter plants or even grown from leaf cuttings.[13] Growing African violets from seed is rare, and most commercially available plants are produced from cuttings and tissue culture.[14]

Flowering

[edit]

The African violet is a day-neutral plant regarding flower development.[15][16]

In culture

[edit]

African violets have become a traditional gift in the developed world. They are often offered for sale at holidays.[14]

They are a popular house plant in many countries, as they can flower during most of the year and are fairly durable to neglect.[17][18]

In the 1997 film Amistad, ex-president John Quincy Adams shows the lead slave Joseph Cinqué his flower collection which contains an African violet which Cinque then recognises from his home land.[citation needed]

References

[edit]
  1. ^ "The Great Merger – Current Taxonomic Status | Gesneriad Reference Web". Retrieved 11 March 2020.
  2. ^ MacDonald, Elvin "The World Book of House Plants" Popular Books
  3. ^ Smithsonian World Checklist of the Gesneriaceae
  4. ^ Burkhardt, Lotte. Verzeichnis eponymischer Pflanzennamen. Erweiterte Edition. 2018.
  5. ^ Darbyshire (2006) Saintpaulia, pp. 50-72, in Beentjy & Ghazanfar (eds), Fl. Trop. East Africa
  6. ^ Pilon F (2012) Saintpaulia. The history and origin of the African Violet.
  7. ^ a b c Nishii, Kanae; Hughes, Mark; Briggs, Marie; Haston, Elspeth; Christie, Frieda; DeVilliers, Margaret J.; Hanekom, Thea; Roos, Wiets G.; Bellstedt, Dirk U. & Möller, Michael (2015). "Streptocarpus redefined to include all Afro-Malagasy Gesneriaceae: Molecular phylogenies prove congruent with geographical distribution and basic chromosome numbers and uncover remarkable morphological homoplasies" (PDF). Taxon. 64 (6): 1243–1274. doi:10.12705/646.8. Retrieved 12 March 2020.
  8. ^ Christenhusz, Maarten J.M. (2012). "On African violets and Cape primroses—towards a monophyletic Streptocarpus (Gesneriaceae)". Phytotaxa. 46: 3–9. doi:10.11646/phytotaxa.46.1.2. Retrieved 12 March 2020.
  9. ^ a b "Search for Saintpaulia". Plants of the World Online. Royal Botanic Gardens, Kew. Retrieved 11 March 2020.
  10. ^ "Grow-African-Violets.com". Retrieved 30 May 2013.
  11. ^ "The Violet Barn". Retrieved 30 May 2013.
  12. ^ Kadohama, Noriaki; Tatsuaki Goh; Miwa Ohnishi; Hidehiro Fukaki; Tetsuro Mimura; Yoshihiro Suzuki (February 2013). "Sudden Collapse of Vacuoles in Saintpaulia sp. Palisade Cells Induced by a Rapid Temperature Decrease". PLOS ONE. 8 (2): e57259. doi:10.1371/journal.pone.0057259. PMC 3581458. PMID 23451194.
  13. ^ Thomas, Paul A. "Growing African Violets". CAES Publications. Retrieved 11 August 2013.
  14. ^ a b Chen, J. "Cultural Guidelines for Commercial Production of African Violets (Saintpaulia ionantha)". University of Florida. Retrieved 13 August 2013.
  15. ^ Modeling Inflorescence Development of the African Violet (Saintpaulia ionantha Wendl.). James E. Faust and Royal D. Heins, J. AMER. SOC. HORT. SCI. 119(4):727–734. 1994.
  16. ^ Saintpaulia ionantha, Stromme E, 1985, p. 48–49. In: A. Halevy (ed.). CRC handbook of flowering. vol. 3. CRC Press, Boca Raton, Fla.
  17. ^ Honan, William H. (26 May 1999). "Lyndon Lyon Is Dead at 94; A Breeder of African Violets". The New York Times. ISSN 0362-4331. Retrieved 15 April 2022.
  18. ^ "African Violets: Why So Popular? | Gesneriad Reference Web". Retrieved 16 April 2022.
[edit]
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