Chrysanthemum is a genus of perennial herbaceous flowering plants — occasionally subshrubs — belonging to the family Asteraceae (order Asterales). The genus was formally established by Linnaeus in 1753 and bears his authority (L.). Most of its species are native to East Asia, with the greatest diversity concentrated in China; a smaller number of species extend into northeastern Europe.
The plants typically bear alternate, divided leaves that are pinnatisect, lobed, or serrate, with hairy-based stalks. Flower heads are arranged in compound arrays, each head consisting of a single row of ray florets (white, yellow, or red) surrounding a cluster of yellow disc florets, all seated on a layered base of phyllaries. The fruit is a ribbed achene.
The genus has a complex taxonomic history. Once encompassing a far broader range of species, it was progressively split into several segregate genera — including Argyranthemum, Glebionis, Leucanthemopsis, Leucanthemum, Rhodanthemum, and Tanacetum — with commercially important florist's chrysanthemums briefly transferred to Dendranthema. A 1999 ruling by the International Botanical Congress restored the florist's chrysanthemums to Chrysanthemum by designating C. indicum as the type species. The most economically significant cultivated hybrid is Chrysanthemum × morifolium (syn. C. × grandiflorum), the florist's chrysanthemum, derived primarily from C. indicum.
With roots in Chinese cultivation stretching back to at least the 15th century BCE, chrysanthemums are among the most historically significant ornamental plants in East Asia. By 2014 more than 20,000 cultivars were recognized globally. The genus is culturally prominent: it is one of the "Four Gentlemen" of Chinese art, the imperial symbol of Japan (the Chrysanthemum Throne), and the subject of hundreds of Chinese poems. Flowers and leaves are also used in culinary traditions across East Asia, and the related insecticidal compound pyrethrum — originally sourced from what was then classified as Chrysanthemum cinerariaefolium — remains economically important.
Etymology
The name Chrysanthemum is derived from the Ancient Greek χρυσός (chrysos, meaning "gold") and ἄνθεμον (anthemon, meaning "flower") — a reference to the yellow flowers of the type species.
Distribution
Chrysanthemum species are native to East Asia and northeastern Europe, with the center of diversity in China. Most wild species are found across temperate regions of East Asia, extending into Japan and the Korean Peninsula.
Ecology
Chrysanthemums are autumn-blooming plants, with flowering typically beginning in early autumn; they are strongly associated with November in temperate Northern Hemisphere climates.
Cultivation
Chrysanthemums have been cultivated in China since at least the 15th century BCE, making them among the oldest ornamental crops in history. Over 500 cultivars were recorded by 1630, and by 2014 more than 20,000 cultivars were recognized worldwide. Cultivation spread to Japan during the Nara and Heian periods (8th–12th centuries), where it flourished through the Edo period and produced highly diverse flower forms. Chrysanthemums entered American horticulture in 1798. For horticultural purposes, all cultivars are classified into 13 divisions by the National Chrysanthemum Society (USA) based on flower form. Over 140 cultivars have received the Royal Horticultural Society's Award of Garden Merit.
Cultural Uses
Chrysanthemums occupy a central place in East Asian culture. In China the flower is one of the "Four Gentlemen" (四君子), a symbol of longevity and nobility, and is particularly significant during the Double Ninth Festival; chrysanthemum tea (菊花茶) brewed from yellow or white blooms of C. morifolium is widely consumed. In Japan the chrysanthemum is the imperial symbol — the Chrysanthemum Throne — and appears on the imperial crest; it is a subject of traditional waka poetry, lacquerware, porcelain, and kimono motifs. In parts of Europe (France, Italy, Poland, Hungary, and others) chrysanthemums are associated with mourning and are traditional offerings for the dead on All Saints' Day. In Australia, white chrysanthemums are worn on Mother's Day. Leaves are eaten as greens in Chinese and Japanese cuisine, and the genus's pyrethrin compounds are an important natural insecticide.
History
The genus was first formally described by Linnaeus in 1753 in Species Plantarum. Cultivation in China began at least by the 15th century BCE and flourished during the Song dynasty. Chrysanthemums reached Japan by the 5th century CE and became the imperial mon during the Kamakura period (12th century). The genus entered Western horticulture in the late 18th century, arriving in the United States in 1798. The International Botanical Congress's 1999 ruling on the type species resolved a decades-long taxonomic dispute over the genus name, returning the widely-grown florist's chrysanthemum to Chrysanthemum from Dendranthema.
Taxonomy Notes
Chrysanthemum was first described by Linnaeus in 1753 (Sp. Pl. 2: 887, Nom. Cons.) and the name is conserved. The genus was substantially narrowed in the late 20th century when several segregate genera were recognized — Argyranthemum, Glebionis, Leucanthemopsis, Leucanthemum, Rhodanthemum, and Tanacetum — and the economically important florist's chrysanthemums were moved to Dendranthema. The 1999 International Botanical Congress ruling re-established C. indicum as the type species, restoring florist's chrysanthemums to Chrysanthemum. GBIF's backbone places the genus in family Asteraceae, order Asterales.
