Dahlia pinnata (D. × pinnata) is a species in the genus Dahlia, family Asteraceae, with the common name garden dahlia. It is the type species of the genus and is widely cultivated.
Description
Dahlia pinnata is a perennial herbaceous plant with a rhizome and tuberous roots, reaching a height of 70 to 120 centimetres (28 to 47 inches), rarely 160 cm. The stem is erect, and branched only in the inflorescence. The leaves are usually simple, with leaflets that are ovate and 5–10 centimetres (2–4 in) long. The plant is slightly shaggy.
Between July and October, atop stems 5 to 15 cm in length are two to eight flower heads, 6 to 10 cm in diameter. The eight florets have a length of 3 to 5 cm, are ovate and coloured pink to deep purple.
↑ Eckehardt J. Jäger, Friedrich Ebel, Peter Hanelt, Gerd K. Müller (ed.): Rothmaler excursion flora of Germany. Volume 5: Herbaceous ornamental and useful plants. Spektrum, Academic Publisher, Heidelberg 2008,
Taxonomy
Hansen and Hjerting in (1996) demonstrated that Dahlia pinnata should more properly be designated D. x pinnata. D. x pinnata was shown to actually be a variant of D. sorensenii that had acquired hybrid qualities before it was introduced to Europe in the sixteenth century and formally named by Cavanilles. The original wild D. pinnata is presumed extinct.
↑ Hansen, H. V. and J. P. Hierting. 1996. Observations on chromosome numbers and biosystematics in Dahlia (Asteraceae, Heliantheae) with an account on the identity of D. pinnata, D.rosea and D. coccinea. Nordic Journal of Botany 16: 445-455.
↑ Cavanilles, A. J. 1791. Icones et Descriptiones Plantarum 1: 57.
Distribution and habitat
It is geographically located in Central America, tending to grow at borders. The plant occurs in Mexico in the mountains around Mexico City.
Ecology
Dahlias tend to attract quite a bit of insects and other animals, some which are dangerous and harmful to their survival. Slugs, earwigs, red spider mites, snails,...
