Camellia


Camellia is a genus of flowering plants in the family Theaceae. They are found in tropical and subtropical areas in eastern and southern Asia, from the Himalayas east to Japan and Indonesia. There are more than 220 described species; almost all are found in southern China and Indochina. Camellias are popular ornamental, tea, and woody-oil plants cultivated worldwide for centuries. Over 26,000 cultivars, with more than 51,000 cultivar names, including synonyms, have been registered or published.
The leaves of C. sinensis are processed to create tea, and so are of particular economic importance in East Asia, Southeast Asia, and the Indian subcontinent, with the processed leaves widely sold and consumed globally. The ornamental C. japonica, C. sasanqua and their hybrids are the source of hundreds of garden cultivars. C. oleifera produces tea seed oil, used in cooking and cosmetics.

Description

Camellias are evergreen shrubs or small trees up to tall. Their leaves are alternately arranged, simple, thick, serrated, and usually glossy.

Flowers and fruit

Their flowers are usually large and conspicuous, one to in diameter, with five to nine petals in naturally occurring species of camellias. The colors of the flowers vary from white through pink colors to red; truly yellow flowers are found only in South China and Vietnam. Tea varieties are always white-flowered. Camellia flowers throughout the genus are characterized by a dense bouquet of conspicuous yellow stamens, often contrasting with the petal colors. Some research has shown that the colour of petals in some species' flowers indicate their size and how they are pollinated; species with red or yellow flowers are pollinated by sunbirds whereas species with white flowers are smaller in diameter and are pollinated by bees.
The fruit of camellia plants is a dry capsule, sometimes subdivided into up to five compartments. Each compartment contains up to eight seeds.

Ecology

Camellia plants are used as food plants by the larvae of some Lepidoptera species. Leaves of Camellia japonica are susceptible to the fungal parasite Mycelia sterile, mycelia sterile PF1022 produces a metabolite named PF1022A that is used to produce emodepside, an anthelmintic drug.
Due to habitat destruction, several camellias have become rare in their natural range. One of these is the aforementioned C. reticulata, grown commercially in thousands for horticulture and oil production but rare enough in its natural range to be considered a threatened species.

Growth

The various species of camellia plants are generally well-adapted to acid soils rich in humus, and most species do not grow well on chalky soil or other calcium-rich soils. Most species of camellias also require a large amount of water, either from natural rainfall or from irrigation, and the plants will not tolerate droughts. However, some of the more unusual camellias - typically species from karst soils in Vietnam - can grow without too much water.
Camellia plants are generally considered slow growing. This slow growth rate makes them well-suited for growing in pots or tubs, and they don't require frequent pruning. While some varieties may grow more quickly than others, particularly when young, the overall growth rate of most camellias is relatively slow. Typically, they will grow about per year until mature - however, this varies depending on their variety and geographical location.

History and use

Camellia sinensis, the tea plant, is of major commercial importance because tea is made from its leaves. The species C. sinensis is the product of many generations of selective breeding to bring out desirable qualities for tea. However, many other camellias can be used to produce a similar beverage. For example, tea made from C. sasanqua leaves is popular in some parts of Japan.
Seeds of C. oleifera, C. japonica, and, to a lesser extent, other species such as C. crapnelliana, C. reticulata, C. sasanqua and C. sinensis as well are pressed to make tea seed oil, a sweet seasoning and cooking oil special to East Asia. It is the most important cooking oil for hundreds of millions of people, particularly in southern China.
Camellia oil is commonly used to clean and protect the blades of cutting instruments.
Camellia oil pressed from seeds of C. japonica, also called tsubaki oil or 2=椿油 in Japanese, has been traditionally used in Japan for hair care. C. japonica plant is used to prepare traditional antiinflammatory medicines.

Garden history

Camellias were cultivated in the gardens of China for centuries before they were seen in Europe. The German botanist Engelbert Kaempfer reported that the "Japan Rose", as he called it, grew wild in woodland and hedgerow, but that many superior varieties had been selected for gardens. Europeans' earliest views of camellias must have been their representations in Chinese painted wallpapers, where they were often represented growing in porcelain pots.
The first living camellias seen in England were a single red and a single white, grown and flowered in his garden at Thorndon Hall, Essex, by Robert James, Lord Petre, among the keenest gardeners of his generation, in 1739. His gardener James Gordon was the first to introduce camellias to commerce, from the nurseries he established after Lord Petre's untimely death in 1743, at Mile End, Essex, near London.
With the expansion of the tea trade in the later 18th century, new varieties began to be seen in England, imported through the British East India Company. The company's John Slater was responsible for the first of the new camellias, double ones, in white and a striped red, imported in 1792. Further camellias imported in the East Indiamen were associated with the patrons whose gardeners grew them: a double red for Sir Robert Preston in 1794 and the pale pink named "Lady Hume's Blush" for Amelia, the lady of Sir Abraham Hume of Wormleybury, Hertfordshire. The camellia was imported from England to America in 1797 when Colonel John Stevens brought the flower as part of an effort to grow attractions within Elysian Fields in Hoboken, New Jersey. By 1819, twenty-five camellias had bloomed in England; that year the first monograph appeared, Samuel Curtis's, A Monograph on the Genus Camellia, whose five handsome folio colored illustrations have usually been removed from the slender text and framed. Though they did not flower for over a decade, camellias that set seed rewarded their growers with a wealth of new varieties. By the 1840s, the camellia was at the height of its fashion as the luxury flower. The Parisian courtesan Marie Duplessis, who died young in 1847, inspired Dumas' La Dame aux camélias and Verdi's La Traviata.
The fashionable imbricated formality of prized camellias was an element in their decline, replaced by the new hothouse orchid. Their revival after World War I as woodland shrubs for mild climates has been paralleled by the rise in popularity of Camellia sasanqua.

Modern cultivars

The tea camellia, C. sinensis, has been selected by many commercial cultivars for the taste of its leaves once processed into tea leaves.
Today, camellias are grown as ornamental plants for their flowers; about 3,000 cultivars and hybrids have been selected, many with double or semi-double flowers. C. japonica is the most prominent species in cultivation, with over 2,000 named cultivars. Next are C. reticulata with over 400 named cultivars, and C. sasanqua with over 300 named cultivars. Popular hybrids include C. × hiemalis and C. × williamsii. Some varieties can grow considerably, up to, though more compact cultivars are available. They are frequently planted in woodland settings alongside other calcifuges, such as rhododendrons. They are particularly associated with areas of high soil acidity, such as Cornwall and Devon in the UK. They are highly valued for their very early flowering, often among the first flowers to appear in the late winter. Late frosts can damage the flower buds, resulting in misshapen flowers.
There is a great variety of flower forms:
  • single
  • semi-double
  • double:
  • * paeony form
  • * anemone form
  • * rose form
  • * formal double

AGM cultivars

The following hybrid cultivars have gained the Royal Horticultural Society's Award of Garden Merit:
NameParentageHeightSpreadFlower colourFlower typeRef.
Cornish Snowcuspidata × saluenensis2.51.5whitesingle
Cornish Springcuspidata × japonica2.51.5pinksingle
Francie L8.08.0rose-pinkdouble
Freedom Bell× williamsii2.52.5redsemi-double
Inspirationreticulata × saluenensis4.02.5rose-pinksemi-double
Leonard Messelreticulata × × williamsii4.04.0rose-pinksemi-double
Royaltyjaponica × reticulata1.01.0light redsemi-double
Spring Festival× williamsii, cuspidata4.02.5pinksemi-double
Tom Knudsenjaponica × reticulata2.52.5deep reddouble paeony
Tristrem Carlyonreticulata4.02.5rose pinkdouble paeony

Taxonomy

The genus was named by Linnaeus after the Jesuit botanist Georg Joseph Kamel, who worked in the Philippines and described one of its species. In 2022 the genus was separated into 7 sections based on phylogenetic study on 161 species. Further studies demonstrated that section Oleifera and Paracamellia should be merged into section Paracamellia. The following sections are currently recognized:
  • Camellia
  • Chrysantha
  • Longipedicellata
  • Longissima
  • Paracamellia
  • Thea
  • Tuberculata

Species

Plants of the World Online currently includes:
  1. Camellia albata Orel & Curry
  2. Camellia amplexicaulis Cohen-Stuart
  3. Camellia amplexifolia Merr. & Chun
  4. Camellia anlungensis Hung T.Chang
  5. Camellia assimiloides Sealy
  6. Camellia aurea Hung T.Chang
  7. Camellia azalea C.F.Wei
  8. Camellia brevistyla Cohen-Stuart
  9. Camellia bugiamapensis Orel, Curry, Luu & Q.D.Nguyen
  10. Camellia campanulata Orel, Curry & Luu
  11. Camellia candida Hung T.Chang
  12. Camellia capitata Orel, Curry & Luu
  13. Camellia cattienensis Orel
  14. Camellia caudata Wall.
  15. Camellia chekiangoleosa Hu
  16. Camellia cherryana Orel
  17. Camellia chinmeiae S.L.Lee & T.Y.A.Yang
  18. Camellia chrysanthoides Hung T.Chang
  19. Camellia concinna Orel & Curry
  20. Camellia connata Craib
  21. Camellia corallina Sealy
  22. Camellia cordifolia Nakai
  23. Camellia costata S.Y.Hu & S.Y.Liang
  24. Camellia costei H.Lév.
  25. Camellia crapnelliana Tutcher - Crapnell's camellia
  26. Camellia crassicolumna Hung T.Chang
  27. Camellia crassipes Sealy
  28. Camellia crassiphylla Ninh & Hakoda
  29. Camellia cuongiana Orel & Curry
  30. Camellia cupiformis T.L.Ming
  31. Camellia curryana Orel & Luu
  32. Camellia cuspidata Bean
  33. Camellia dalatensis V.D.Luong, Ninh & Hakoda
  34. Camellia debaoensis R.C.Hu & Y.Q.Liufu
  35. Camellia decora Orel, Curry & Luu
  36. Camellia dilinhensis Ninh & V.D.Luong
  37. Camellia dongnaicensis Orel
  38. Camellia dormoyana Sealy
  39. Camellia drupifera Lour.
  40. Camellia duyana Orel, Curry & Luu
  41. Camellia edithae Hance
  42. Camellia elizabethae Orel & Curry
  43. Camellia elongata Rehder
  44. Camellia erubescens Orel & Curry
  45. Camellia euphlebia Merr. ex Sealy
  46. Camellia euryoides Lindl.
  47. Camellia fangchengensis S.Ye Liang & Y.C.Zhong
  48. Camellia fansipanensis J.M.H.Shaw, Wynn-Jones & V.D.Nguyen
  49. Camellia fascicularis Hung T.Chang
  50. Camellia flava Sealy
  51. Camellia flavida Hung T.Chang
  52. Camellia fleuryi Sealy
  53. Camellia fluviatilis Hand.-Mazz.
  54. Camellia forrestii Cohen-Stuart
  55. Camellia fraterna Hance
  56. Camellia furfuracea Cohen-Stuart
  57. Camellia gaudichaudii Sealy
  58. Camellia gilbertii Sealy
  59. Camellia glabricostata T.L.Ming
  60. Camellia gracilipes Merr. ex Sealy
  61. Camellia grandibracteata Hung T.Chang, Y.J.Tan, F.L.Yu & P.S.Wang
  62. Camellia granthamiana Sealy - Grantham's camellia
  63. Camellia grijsii Hance
  64. Camellia gymnogyna Hung T.Chang
  65. Camellia harlandii Orel & Curry
  66. Camellia hatinhensis V.D.Luong, Ninh & L.T.Nguyen
  67. Camellia hekouensis C.J.Wang & G.S.Fan
  68. Camellia hiemalis Nakai
  69. Camellia honbaensis Luu, Q.D.Nguyen & G.Tran
  70. Camellia hongiaoensis Orel & Curry
  71. Camellia hongkongensis Seem.
  72. Camellia hsinpeiensis S.S.Ying
  73. Camellia huana T.L.Ming & W.J.Zhang
  74. Camellia ilicifolia Y.K.Li
  75. Camellia impressinervis Hung T.Chang & S.Ye Liang
  76. Camellia indochinensis Merr.
  77. Camellia ingens Orel & Curry
  78. Camellia insularis Orel & Curry
  79. Camellia × intermedia Nagam.
  80. Camellia inusitata Orel, Curry & Luu
  81. Camellia japonica L. - East Asian camellia
synonym Camellia rusticana - snow camellia
  1. Camellia kissii Wall.
  2. Camellia krempfii Sealy
  3. Camellia kwangsiensis Hung T.Chang
  4. Camellia lanceolata Seem.
  5. Camellia langbianensis P.H.Hô
  6. Camellia laotica T.L.Ming
  7. Camellia lawii Sealy
  8. Camellia leptophylla S.Ye Liang ex Hung T.Chang
  9. Camellia ligustrina Orel, Curry & Luu
  10. Camellia longicalyx Hung T.Chang
  11. Camellia longii Orel & Luu
  12. Camellia longipedicellata Hung T.Chang & D.Fang
  13. Camellia longissima Hung T.Chang & S.Ye Liang
  14. Camellia lucii Orel & Curry
  15. Camellia lutchuensis T.Itô
  16. Camellia luteocerata Orel
  17. Camellia luteoflora Y.K.Li ex Hung T.Chang & F.A.Zeng
  18. Camellia luteopallida V.D.Luong, T.Q.T.Nguyen & Luu
  19. Camellia luuana Orel & Curry
  20. Camellia maiana Orel
  21. Camellia mairei Melch.
  22. Camellia maoniushanensis J.L.Liu & Q.Luo
  23. Camellia megasepala Hung T.Chang & Trin Ninh
  24. Camellia melliana Hand.-Mazz.
  25. Camellia micrantha S.Ye Liang & Y.C.Zhong
  26. Camellia mileensis T.L.Ming
  27. Camellia mingii S.X.Yang
  28. Camellia minima Orel & Curry
  29. Camellia mollis Hung T.Chang & S.X.Ren
  30. Camellia montana Hung T.Chang & S.X.Ren
  31. Camellia murauchii Ninh & Hakoda
  32. Camellia namkadingensis Soulad. & Tagane
  33. Camellia nematodea Sealy
  34. Camellia nervosa Hung T.Chang
  35. Camellia oconoriana Orel, Curry & Luu
  36. Camellia oleifera C.Abel - oil-seed camellia, tea oil camellia
  37. Camellia pachyandra Hu
  38. Camellia parviflora Merr. & Chun ex Sealy
  39. Camellia parvimuricata Hung T.Chang
  40. Camellia paucipunctata Chun
  41. Camellia petelotii Sealy synonyms:
C. chrysantha, C. nitidissima - yellow camellia
  1. Camellia philippinensis Hung T.Chang & S.X.Ren
  2. Camellia pilosperma S.Yun Liang
  3. Camellia pingguoensis D.Fang
  4. Camellia piquetiana Sealy
  5. Camellia pitardii Cohen-Stuart
  6. Camellia pleurocarpa Sealy
  7. Camellia polyodonta F.C.How ex Hu
  8. Camellia psilocarpa X.G.Shi & C.X.Ye
  9. Camellia ptilophylla Hung T.Chang
  10. Camellia pubicosta Merr.
  11. Camellia pubifurfuracea Y.C.Zhong
  12. Camellia pubipetala Y.Wan & S.Z.Huang
  13. Camellia pukhangensis N.D.Do, V.D.Luong, S.T.Hoang & T.H.Lê
  14. Camellia punctata Cohen-Stuart
  15. Camellia pyriparva Orel & Curry
  16. Camellia pyxidiacea Z.R.Xu, F.P.Chen & C.Y.Deng
  17. Camellia quangcuongii L.V.Dung, S.T. Hoang & Nhan
  18. Camellia reflexa Orel & Curry
  19. Camellia renshanxiangiae C.X.Ye & X.Q.Zheng
  20. Camellia reticulata Lindl.
  21. Camellia rhytidocarpa Hung T.Chang & S.Ye Liang
  22. Camellia rosacea Tagane, Soulad. & Yahara
  23. Camellia rosiflora Hook.
  24. Camellia rosmannii Ninh
  25. Camellia rosthorniana Hand.-Mazz.
  26. Camellia rubriflora Ninh & Hakoda
  27. Camellia salicifolia Champ.
  28. Camellia saluenensis Stapf ex Bean
  29. Camellia sasanqua Thunb.
  30. Camellia scabrosa Orel & Curry
  31. Camellia sealyana T.L.Ming
  32. Camellia semiserrata C.W.Chi
  33. Camellia septempetala Hung T.Chang & L.L.Qi
  34. Camellia siangensis T.K.Paul & M.P.Nayar
  35. Camellia sinensis Kuntze – tea plant
  36. Camellia sonthaiensis Luu, V.D.Luong, Q.D.Nguyen & T.Q.T.Nguyen
  37. Camellia stuartiana Sealy
  38. Camellia subintegra P.C.Huang
  39. Camellia synaptica Sealy
  40. Camellia szechuanensis C.W.Chi
  41. Camellia szemaoensis Hung T.Chang
  42. Camellia tachangensis F.S.Zhang
  43. Camellia tadungensis Orel, Curry & Luu
  44. Camellia taliensis Melch. – also used to make tea like C. sinensis
  45. Camellia tenii Sealy
  46. Camellia thailandica Hung T.Chang & S.X.Ren
  47. Camellia thanxaensa Hakoda & Kirino
  48. Camellia tienyenensis Orel & Curry
  49. Camellia tomentosa Orel & Curry
  50. Camellia tonkinensis Cohen-Stuart
  51. Camellia transarisanensis Cohen-Stuart
  52. Camellia trichoclada S.S.Chien
  53. Camellia tsaii Hu
  54. Camellia tsingpienensis Hu
  55. Camellia tuberculata S.S.Chien
  56. Camellia tuyenquangensis V.D.Luong, Le & Ninh
  57. Camellia uraku Kitam.
  58. Camellia villicarpa S.S.Chien
  59. Camellia viridicalyx Hung T.Chang & S.Ye Liang
  60. Camellia viscosa Orel & Curry
  61. Camellia vuquangensis V.D.Luong, Ninh & L.T.Nguyen
  62. Camellia wardii Kobuski
  63. Camellia xanthochroma K.M.Feng & L.S.Xie
  64. Camellia yokdonensis Dung bis & Hakoda
  65. Camellia yunkiangica Hung T.Chang, H.S.Wang & B.H.Chen
  66. Camellia yunnanensis Cohen-Stuart

Fossil record

The earliest fossil record of Camellia are the leaves of †C. abensis from the upper Eocene of Japan, †C. abchasica from the lower Oligocene of Bulgaria and †C. multiforma from the lower Oligocene of Washington, United States.

Cultural significance

The Camellia family of plants in popular culture.