Carnations (Dianthus caryophyllus) were mentioned in Greek literature 2,000 years ago. "Dianthus" was coined by Greek botanist Theophrastus, and is derived from the Greek words for divine ("dios") and flower ("anthos"). Some scholars believe that the name "carnation" comes from "coronation" or "corone" (flower garlands), as it was one of the flowers used in Greek ceremonial crowns. Others think the name stems from the Latin "caro" (genitive "carnis") (flesh), which refers to the original colour of the flower, or incarnatio (incarnation), which refers to the incarnation of God made flesh.
Carnations is a herbaceous perennial plant growing to 80 cm tall. The leaves are glaucous greyish green to blue-green, slender, up to 15 cm long. The flowers are produced singly or up to five together in a cyme; they are 3–5 cm diameter, and sweetly scented; the original natural flower color is bright pinkish-purple, but cultivars of other colours, including red, white, yellow and green, have been developed.
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Carnations do not naturally produce the pigment delphinidin, thus a blue carnation cannot occur by natural selection or be created by traditional plant breeding. It shares this characteristic with other widely sold flowers like roses, lillies, chrysanthemums and gerberas.
Around 1996 a company used genetic manipulation to extract certain genes from petunia and snapdragon flowers to produce a blue-mauve carnation, which was commercialized as Moondust. In 1998 a violet carnation called Moonshadow was commercialized. As of 2004 three additional blue-violet/purple varieties have been commercialized.
For the most part, carnations express love, fascination, and distinction, though there are many variations dependent on color. Light red carnations represent admiration, while dark red carnations denote deep love and affection. White carnations represent pure love and good luck, while striped (variegated) carnations symbolize regret that a love cannot be shared. Purple carnations indicate capriciousness. In France, it is a traditional funeral flower, given in condolence for the death of a loved one. In France and Francophone cultures, carnations symbolize misfortune and bad luck. Carnation is the birth flower for those born in the month of January. Pink carnations have the most symbolic and historical significance. The pink carnation became the symbol of a mother's undying love.
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In Korea, red and pink Carnations are used for showing their love and gratitude toward their parents on Parents Day (Korea does not separate Mother's Day and Father's Day, but has Parents Day on 8 May). Sometimes, you can see parents wear a corsage of Carnation(s) on their left chest on Parents Day. Not only on Parents Day, but also on Teacher's Day (15 May), people express their admiration and gratitude to their teachers with Carnations, as Carnation has the meaning of 'admiration', 'love', and 'gratitude'.
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Green carnations are for St. Patrick's Day and were famously worn by the Irish writer Oscar Wilde. The green carnation thence became a symbol of homosexuality in the early 20th century.
At Oxford University, carnations are traditionally worn to all examinations; white for the first exam, pink for exams in between and a red for the last exam. Originally this was a white carnation that was kept in a red inkpot between exams, so by the last exam it was fully red. It is thought to originate in the late 1990s. [source : Carnations]