Wild morning glories have been traced back to ancient China where they were used for ceremonies as well as for making medicines. According to the Massachusetts Institute of Technology (MIT), Aztec civilizations used the juice of some of the Central American morning glory species to create rubber-like substances.
Mostly, the Morning Glory is considered as a symbol of love and affection. Morning glory flowers represent the month of September and are used for 11th wedding anniversaries.
Japan has been one of the world’s prime horticultural centers since mediaeval times, and the morning glory (Asagao) has traditionally been one of the chief species to be cultivated in this region.
Morning glory is considered to have been brought over from China as a Chinese medicine during the Nara era (710-784). In the beginning it was called Kengo while its seed Kengosi (or Kenigosi). Later it came to be called the morning glory, perhaps for the reason that its gorgeous flower opened early in the morning.
The morning glory flower turned out to be a subject of aesthetic approbation. The morning glory became a favorite flower of the common people of Japan during the Edo era (1615-1868). The Japanese haiku, joururi (a kind of musical narrative), kabuki, and others witnessed its appearance at that time.
The original blue flower was portrayed in “Heike Noukyou”, a collection of decorated scrolls of Buddhist sutra dedicated to the Itukusima Shrine in 1164 by the Taira family.
A white flower seems to have appeared prior to the Edo era; however it was not documented until 1664. White, red, asagi (light blue), and azure flowers, as well as futaba asagao (a dwarf morning glory), were documented by the end of the 17th century. “Buturuihinsitu” (Collections of herbs and natural products) by Gennai Hiraga (1762, Houreki 12) has descriptions about a black-and-white flecked flower (somewake) and a double flower, while in “Honzoukoumokukeimou” (Enlightening outline of natural materials for medicinal use) in 1803 (Kyouwa 3), Split, Swertia-like, and pear flowers are described.
The creation and maintenance of a huge number of mutant morning glory strains is a feature of the “Japanese morning glory cultivation of the late Edo period”, making it unique in world horticultural history. The tradition has been carried forward through the Meiji, Taisho, and Showa periods, leaving a unique impression in the cultures of each era.
The latter Edo period shows more than one booms in cultivation of varied morning glory. In the first boom, during the Bunka/Bunsei era (1804-1829), many new mutants appeared. “Asagao-hinruizuko”, “Kadan-asagao-tuu”, ” Asagaoso”, and “Teityu-asagao-hu”, were some of the morning glory specialty picture books published from Bunka 12 (12th year of the Bunka era) to Bunka 14 (1816-1818).
In the second boom during the Kaei/Ansei era (1848-1860), new variants for example rangiku (polymorphic), rinpuu (brown) and swallow (miniature) appeared. The main trend of in cultivation features combining many already-existing mutants with the botan flower (a kind of double flower consisting of petalled stamens and pistils). The varied flowers of the Japanese morning glory displayed more intricacy and beauty. Particularly, “Santo-ittyo” and “Asagao 36 kasen” published in Kaei 7 (1854), and “Tohi-syuukyou” published in Ansei 4 (1857) portrayed the combination of novel flowers saizaki, sisizaki, and daizaki with botan flower. Moreover, other variants were combined which resulted in compound flowers with strange leaves.