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DAHLIA , a genus of herbaceous See also:plants of the natural See also:order See also:Compositae, so called after Dr See also:Dahl, a See also:pupil of See also:Linnaeus. The genus contains about nine See also:species indigenous in the high sandy plains of See also:Mexico. The dahlia was first introduced into See also:Britain from See also:Spain in 1789 by the marchioness of See also:Bute. The species was probably D. variabilis, whence by far the See also:majority of the forms now See also:common have originated. The See also:flowers, at the See also:time of the first introduction of the plant, were single, with a yellow disk and dull See also:scarlet rays; under cultivation since the beginning of the 19th See also:century in See also:France and See also:England, flowers of numerous brilliant hues have been produced. The See also:flower has been modified also from a See also:flat to a globular shape, and the arrangement of theflorets has been rendered quite distinct in the See also:ranunculus and See also:anemone-like kinds. The See also:ordinary natural height of the dahlia is about 7 or 8 ft., but one.of the See also:dwarf races grows to only 18 in. With changes in the flower, changes in the shape of the See also:seed have been brought about by cultivation; varieties of the plant have been produced which require more moisture than others; and the See also:period of flowering has been made considerably earlier. In 18o8 dahlias were described as flowering from See also:September to See also:November, but some of the dwarf varieties at See also:present grown are in full blossom in the See also:middle of See also:June. The large number of varieties may be classed as under the following heads: (I) Single dahlias. These have been derived from D. coccinea; they have a disk of tubular florets surrounded by the large showy See also:ray florets. (2) Show dahlias, large and See also:double with flowers self-coloured or See also:pale-coloured and edged or tipped with a darker See also:colour. (3) See also:Fancy dahlias, resembling the show but having the florets striped or tipped with a second tint. (4) Bouquet or Pompon dahlias, with much smaller double flowers of various See also:colours. (5) See also:Cactus dahlias, derived from D. Juarezi, a See also:form which has given rise to a beautiful See also:race with pointed starry flowers. (6) See also:Paeony flowered dahlias, a new but not See also:pretty race, with large floppy heads, broad florets and several disk florets in centre.
New varieties are procured from seed, which should be sown in pots or pans towards the end of See also: They may stand singly like common border flowers, but have the most imposing See also:appearance when seen in masses arranged according to their height. Florists usually devote a See also:plot of ground to them, and plant them in lines 5 to 10 ft. apart. This is done about the beginning of June, sheltering them if necessary from See also:late frosts by inverted pots or in some other convenient way. Old roots often throw up a multitude of stems, which render thinning necessary. As the plants increase in height, they are furnished with strong stakes, to secure them from high winds. Dahlias flower on till they are interrupted by See also:frost in autumn. The roots are then taken up, dried, and stored in a cellar, or some other See also:place where they may be secure from frost and moisture. See also:Ear-wigs are very destructive, eating out the young buds and florets. Small flower-pots See also:half filled with dry See also:moss and inverted on stakes placed among the branches, form a useful See also:trap. Additional information and CommentsThere are no comments yet for this article.
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