AN ENCYCLOPEDIA OF HORTICULTURE. 



431 



Daemonorops continued. 



D. omatns (adorned). A very pretty species, baring finely-cut 

 pinnate leaves. At present, it is very rare. Java, 1875. 



D. palembanicus (Palembang). 1. pinnate, broadly ovate; 

 pinnae numerous, narrow, elongated; petioles erect, armed at 

 the back with somewhat stout deflexed spines, which are 

 thickened at the base ; young leaves of a bright cinnamon 

 brown. Sumatra, 1872. 



D. periacanthus (ring-spined). I broadly ovate, pinnate; 

 petioles furnished with numerous spines, which are set on in 

 irregular rings ; young leaves nearly straw-coloured, h. 16ft. 

 Sumatra, 1872. This species resembles D. paUmbanicut. 



D. plnmosus (plumed).* I. of a rich dark green, remarkably 

 plume-like, pinnate, 2ft to 4ft. or more in length ; pinna 1ft 

 long, less than lin. wide, tapering to a narrow point, pendent ; 

 petioles densely armed with stout black spines, which are white 

 at the base. India, 1870. A very elegant species. 



DAFFODIL. See Narcissus. 



DAHLIA (named after Dr. Dahl, a Swedish botanist, 

 and pupil of Linnaeus). STN. Georgina. OBD. Composites. 

 A popular genus of herbaceous plants, having a double 

 involucre, no pappus, and a large scarious bracteole at 

 the base of each floret. There are but a Bmall number 

 of species, and all are natives of Mexico and Central 

 America. 



The Dahlia was first introduced into this country from 

 Spain, in 1789, by the Marchioness of Bute. This im- 

 portation, and another made by Lady Holland, in 1804, 

 were, however, lost to cultivation. A third stock was 

 afterwards brought from France, about the year 1815, 

 and from this the numerous forms have been obtained. 

 It is most probable that nearly all the types and varie- 

 ties of the common garden Dahlia now in cultivation 

 have originated from D. coccinea (see Fig. 602), D. 

 Herclii (see Fig. 605), and D. variabvUs (see Fig. 606). 

 Being among the best of outside autumn-flowering plants, 

 and, moreover, easily propagated and grown, Dahlias form 

 indispensable subjects for flower-garden decoration, suit- 

 able for those of either large or small dimensions. 



There are four important classes into which Dahlias 

 may be divided, in addition to a few minor ones, con- 

 taining only a limited number of representatives. These 

 are known as Show, Fancy, Bouquet or Pompone, and 

 Single-flowered. D. Juarezii represents a small class, 

 with semi-double flowers, distinct from any of the others. 

 D. excelsa and D. imperialis reach a great height before 

 flowering, and are best grown in pots for greenhouse 

 decoration in autumn and winter. Show Dahlias are all 

 double, and require to have large flowers of the most 

 perfect form to be considered good. Selfs and pale- 

 coloured flowers, edged or tipped with a darker colour, 

 are included under Show varieties. Flowers of a similar 

 size, but having florets dark-coloured at the base, and 

 tipped or striped with a paler colour or white, are known 

 as Fancy varieties. The Bouquet or Pompone, also those 

 sometimes termed the Bedding section, have double 

 flowers of a much smaller size ; various colours are in- 

 cluded, and all are invariably very pretty ; the habit 

 is dwarf and compact, constituting these the best for 

 bedding purposes, and the flowers are most useful for 

 cutting, when Double ones are required. The Single- 

 flowered varieties have again become very popular, and 

 are amongst the most beautiful and useful subjects for 

 cut flowers. The form and size of flower-heads in all 

 the sections have now attained a high degree of excel- 

 lence. White, yellow, red, and purple, with a great 

 variety between of these colours intermixed, are also 

 represented in each of the large classes. 



PROPAGATION. Dahlias are propagated by seeds, cut- 

 tings, division of the roots, and sometimes by grafting. 



Seeds. These are produced by the Single varieties in 

 large quantities, but not so freely by the Doubles. Ob- 

 taining seeds from the latter is mostly restricted to 

 florists who make this plant a speciality, and who do 

 it with a view to raising new varieties. The colours 

 of the Single flowers are reproduced by this method 



Dahlia continued. 



tolerably true to character, and only those that are good 

 should be selected from which to save seed. Sow thinly in 



I pans, at the end of March, and place on a hotbed or in 

 a propagating house. The seedlings will soon appear, 



1 and should then be placed singly in pota, and grown 

 on for a time in the same temperature. Repot as 

 becomes requisite, and gradually harden off in a cool 

 frame, ready for putting outside at the end of May. If 

 liberally treated, large plants and good flowers may be 

 obtained the first season. 



Cuttings. This is the method of propagation usually 

 adopted, and is easily accomplished in spring. The roots 

 having been stored and kept dry in winter, should be 

 introduced to bottom heat at the beginning of February, 

 and these, but not the crowns, should be covered with soil 

 A slight syringing daily will be sufficient to induce the pro- 

 duction of shoots, and each of these may be removed, if 

 required, as soon as it has two joints. If placed singly 

 in small pots of light leaf soil and sand, and plunged in 

 a close frame, roots will soon be emitted, and the plants 

 may be hardened, repotted, and transferred to cooler 

 positions, as recommended for seedlings. Cuttings of 

 Dahlias root best when taken in this way quite young; 

 and, as a succession soon appears, any variety may be 

 readily increased. The tops of the young shoots also 

 strike freely in summer. 



Division of Roots. All Dahlias have several fleshy 



FIG. 600. DAHLIA, FLESHY ROOTSTOCK. 



tuber-like roots (see Fig. 600) that may be separated singly 

 for propagating after they are started in spring, allowing 



FIG. 601. DAHLIA BOOTS, divided for Propagating. 



one shoot to each (see Fig. 601). If these are inserted in 

 large pots, vigorous plants may be obtained for placing 

 outside later on; but the quantity will be limited to the 

 number of tubers when divided, and will not generally 

 be so many in the end as might have been procured from 

 cuttings. 



Grafting is occasionally practised for preserving new 

 varieties throughout the winter, when otherwise there 

 would be a danger of losing them. The plan ia to take 

 a shoot with two joints, cut it below the bottom one, and 

 remove a portion of the skin on one side. A fleshy 

 root from a hardier sort should be prepared, by having 

 a similar-sized hole or incision made for the reception 

 of the graft. This should be tied in, and the matting 

 covered over with clay, the whole being afterwards potted 

 and placed under a hand glass until a union has taken 

 place. To keep the scion alive in winter, it must be 

 kept growing slowly, and cuttings from it may be obtained 

 in spring. This system of propagation is not often re- 

 sorted to. 



CULTIVATION. Being vigorous-growing plants, Dahlias 

 require a rich, moderately heavy soil to give the best 

 results; but their cultivation will often prove successful 

 under conditions widely varied in this respect. When it 



