As a common name, though, ‘chrysanthemum’ will always be understood by gardeners to refer to the group of showy hybrid plants derived from east Asian species now classified under Dendranthema. The situation arose because Linnaeus’ original or ‘type’ species of his genus Chrysanthemum was the European corn marigold, C. segetum—when the genus was later split up, it was with this and its close relatives that the name Chrysanthemum had to stick. Below are listed genus headings under which the former 'chrysanthemums' should be sought, in order of horticultural importance.
 
Dendranthema: The showy 'florist's chrysthanthemums', often sold in pots and running into a vast number of cultivars, mostly double-flowered in a range of strong colors. They are derived from several East Asian species and were brought from China to Europe in the late eighteenth century.
 
Argyranthemum: The marguerites or marguerite daisies, evergreen subshrubs from the Canary Islands and Madeira, with many cultivars in pastel pinks and yellows as well as white.
 
Leucanthemum: A large group of herbaceous perennials from the Mediterranean and Europe, all white-flowered and non-aromatic, including the Shasta daisy and ox-eye daisy.
 
Tanacetum: Another large group of perennials and subshrubs, also from Europe, North Africa and temperate Asia, with very aromatic foliage and white yellow or red flowers. It includes tansy (T. vulgare), the commercial pyrethrum (T. cinerariifolium), feverfew (T. parthenium), and many other cottage garden and rock-garden plants.
 
Pyrethropsis: Includes a number of Mediterranean perennials and subshrubs with long-stalked white or pink flowerheads, some grown as ornamentals including P. gayana.
 
Ajania: Perennials from eastern and central Asia, similar to Dendranthema but with flowerheads lacking large ray-florets. One species, A. pacifica, is sometimes grown.
 
 Hardiness zone from 7 To 11
 Plant Spread approx. 30 cm
 Plant Height From approx. 60 To 120 cm
 Flowering colors: Red, White, Yellow
 Flowering season: Spring, Summer, Autumn, Winter
 Garden type: Bedding Plant, Small Garden
 Position: Sunny
 Propagation season: Spring, Autumn
 Soil: Sandy Loam, Medium Loam, Clay Loam,
 
Chrysanthemum
Cultivation: The true chrysanthemums are easily grown annuals, requiring little more than a moist, fertile, well-tilled soil and a sunny position. They prefer climates with fairly cool summers but in warmer, drier climates can be timed to bloom in winter. Propagate from seed, sown in fall (autumn) or early spring.
 
  Botanica Plus
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