Division of Roots
All Dahlias have several fleshy tuber-like roots that may be separated singly for propagating after they are started in spring, allowing one shoot to each. 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 is 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 resorted 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 is proposed to plant in masses, the ground should be trenched, and manure added if the soil is naturally poor. It is not advisable to apply strong manure in spring, as over-luxuriance in foliage would thereby be encouraged at the expense of the production of flowers. A light, open position, free from the shade of trees, is best; but surrounding shrubs or dwarf plants are often an advantage to Dahlias by protecting them from high winds. Mixed flower borders, backed up with shrubs, are good positions, and a fine effect may be produced in autumn, especially with the best of the Single varieties, by planting in masses, such as large circular beds. The Dwarf Pompone section is best adapted for use in smaller beds, and these, or others, may be kept still lower by pegging down when young. Planting out should not be attempted before the beginning of June, in most localities, as the least exposure to frost causes much injury. The heights of the different varieties must be ascertained, and their respective positions fixed accordingly. From 3ft. to 6ft. apart is none too much space for strong, tall-growing varieties. Seedlings, or late-struck cuttings, will not require quite so much. Water well after planting, and apply a temporary stake to each, for a time. Dahlias are much benefited by frequent applications of water during summer, and by liquid manure after the buds are formed. If exhibition blossoms are required, the shoots and flower buds must be thinned out in the younger stages of growth; but otherwise it will be unnecessary to do so. Permanent stakes of about 4ft. in height, must replace the others when the plants are established and growing. The most useful Dahlias to cultivate for cut flowers are the Single and Pompone sections; and the most distinct and highly-coloured sorts should be selected.
Storing. Dahlias may remain in the ground until the tops are destroyed by frost, when they should be cut down to within 6in. of the ground, and afterwards lifted. Remove as much soil as possible with a pointed stick, attach the label of each to the stem, and store away in a dry, cool, frost-proof place. Looking over occasionally to remove any part of the roots that may be damping, is all that is required until starting again the following spring. Young plants, raised either from seeds or cuttings, will supply large roots in the autumn of the same season. INSECTS. Earwigs are most destructive to Dahlias, by eating out the young points of the shoots, and afterwards the florets, before they are developed. Small flowerpots, half-filled with dry moss, and inverted on the tops of the stakes, or hollowed bean stalks placed amongst the branches, are the best-known traps. They should be examined each morning, and any Earwigs found therein destroyed.
A list of the species, and the most striking of what may be called the "botanical" varieties, is given below.
D. bidentifolia (bidentate-leaved). A synonym of D. coccinea. D. coccinea (scarlet). fl.-heads with scarlet ray-florets and yellow disk; outer involucral bracts five, reflexed; inner series numerous. Autumn. l. pinnate, scabrous. h. 3ft. to 4ft. SYNS. D. bidentifolia and Georgina Cervantesii. (B. M. 762.) D. crocata (yellow). A synonym of D. variabilis.
D. excelsa (tall). fl.-heads pale lilac-purple, 4in. across. l. doubly pinnatipartite, 2 1/2ft. long by about 2ft. broad. Stem perennial, very thick, becoming woody, growing to the height of 20ft. and upwards, less branched, and assuming more the aspect of a tree than any other species. (B. 88.) D. glabrata (smooth). A synonym of D. Mercki.
D. gracilis (slender). fl.-heads brilliant orange-scarlet; involucral bracts small, narrow. Summer and autumn. l. bipinnate, glabrous; leaflets ovate, coarsely crenate. h. 4ft. to 5ft. (R. G. 861.) D. imperialis (imperial).* fl.-heads white, tinged with lilac, and streaked with blood-red at the base, drooping, bell-shaped; disposed in large spreading panicles, 3ft. to 5ft. across. h. 10ft. to 12ft. Mexico, 1863. This remarkable and beautiful species, from its not flowering till late in the autumn, does not fully perfect itself out of doors, and should, consequently, be removed to the greenhouse or conservatory early in October. (B. M. 5183.) D. Juarezii (Juarez's).* Cactus Dahlia. fl.-heads brilliant scarlet; florets overlapping each other, and varying in length, thus giving the flower an irregular appearance. h. 3ft. A form which originated under cultivation in Mexico. Very distinct and remarkable; well worth the most extensive cultivation.
D. Mercki (Merck's). fl.-heads white and yellow, or lilac and yellow, small, with a good outline. October. h. 2ft. to 4ft. 1839. SYN. D. glabrata., for which we are indebted to Mr. T. S. Ware. (B. M. 3878.) D. M. Decaisneana (Decaisne's). fl.-heads purple, with a golden disk, small, numerous. l. pinnate, divided. h. 3ft. (R. H. 1864, 31.) D. superflua (superfluous). A synonym of D. variabilis. D. variabilis (variable). fl.-heads very variable. August and September. 1789. This is probably the first species introduced, and whence by far the majority of forms now very common, have originated. In the wild state, the central, or disk florets are said to be yellow, small, and tubular, and the marginal, or ray florets, only conspicuous and highly coloured in some shade of scarlet. SYNS. D. crocata, D. superflua.
D. viridiflora (green-flowered). fl.-heads pure self-green, Pompone size, double, and full-petalled. A curious monstrosity, of garden origin. VARIETIES. Subjoined is a large selection of the best garden Dahlias cultivated at the present time, including many of the new ones distributed in 1884. As good varieties are numerous, and additional improved forms in some way obtained annually in each section, it is more than likely that others of equal merit have been omitted. The varieties with single flowers being now so numerous, a classification has been arranged and adopted by Mr. T. S. Ware, of Tottenham, who makes these plants a speciality (and to whom we are indebted for Figs. 607 to 611), for grouping them into four sub-divisions or classes, according to the shape of the flowers. Fig. 607 represents two varieties of the section with Stellate or Star-like flowers; these are rather small, but very floriferous, and of a dwarf bushy habit. Another form is shown in Fig. 608, where the flowers are Flat. Fig. 609 shows those with beautifully Reflexed flowers, that are invariably solid and massive, and well adapted for exhibition. The fourth, and last, group is represented in Figs. 610 and 611, where the flowers are only Slightly Reflexed; these come between the Flat and the Much Reflexed sections, and include some fine varieties for exhibition. The figures are only intended to represent the classification of the flowers according to their shape, and do not refer to the colours, as a great diversity of these is included in each group. Many are self-coloured; others, which are edged, blotched or striped, are termed Fancy varieties of the Single-flowered class.
Show Varieties. ACME OF PERFECTION, primrose-yellow; ALEXANDER CRAMOND, maroon, shaded crimson, good; ARBITRATOR, delicate fawn; AURORA, golden-buff, distinct; BESSIE, lilac, full; BURGUNDY, dark puce, suffused light purple, good; CARDINAL, rich scarlet, full, of fine form; CHARLES LIDGARD, deep yellow, edged crimson; CHARLES TURNER, yellow, edged and tipped crimson; CHARLOTTE DORLING, large white, tipped; CONDOR, peculiar colour, buff, shaded orange; COUNTESS OF LONSDALE, rosy-lilac; CREAM OF THE VALLEY, cream tinged salmon, fine form; CRITERION, bright rose, good; CROWN PRINCE, pale buff, full; DAUNTLESS, dark orange, shaded; DELIGHT, creamy-white, edged purple; DEWDROP, deep primrose; DUKE OF ALBANY, rich crimson, fine form; EDWARD PURCHASE, bright crimson; ETHEL BRITTEN, blush-white, edged purple; FLAG OF TRUCE, white, tipped lilac; FRANK RAWLINGS, purplish-magenta, fine flower; GEORGE RAWLINGS, dark maroon, finely cupped; GOLDFINDER, yellow, tipped red; GRAND NATIONAL, yellow, very fine, new; HERBERT TURNER, white, tinged lilac; HOPE, bright rosy-lilac, large; H. W. WARD, yellow, heavily edged with crimson; IMPERIAL, deep purple, shaded lilac, fine form; JAMES COCKER, large, purple, very fine; JAMES VICK, purplish-maroon; JOHN COCKER, glossy black; JOHN NEVILLE KEYNES, fine yellow; JOHN WYATT, deep scarlet; JULIA WYATT, creamy-white, large and good; LEAH, golden-yellow; LILLIE WARD, white, tinged pale rose; MAJOR CORNWALLIS WEST, scarlet, shaded orange; MRS. GLADSTONE, delicate soft pink, new and very fine; MRS. HARRIS, white, edged pale lilac, good; MRS. HENSHAW, white, large and full; MRS. P. WYNDHAM, yellow, edged rosy-purple; MRS. W. HASKINS, fawn, distinct and good, new; MURIEL, fine clear yellow, new; OVID, rich purple, extra good; ROSETTA, large purple; RUBY GEM, ruby-crimson, small yellow tip, new; SHIRLEY HIBBERD, dark crimson; STATESMAN, purplish-crimson, new; SUNBEAM, bright clear buff, good form; THOMAS GOODWIN, dark maroon; WALTER H. WILLIAMS, bright scarlet, large and fine; WILLIAM RAWLINGS, rich crimson-purple.
Fancy Varieties. ALDERMAN, lilac, striped and spotted purple, new; ANNIE RAWLINGS, pure white, striped lake; ARABELLA, buff, scarlet and crimson stripes, new; BARNABY RUDGE, fawn, spotted crimson; BEAUTY, yellow, tipped rose; CHARLES WYATT, rose, flaked crimson; CHORISTER, fawn, striped crimson and rose; DRAGON, yellow, striped bright crimson; DUCHESS OF ALBANY, pale orange, rich crimson stripes, new; FANNY STURT, red, tipped white; FLORA WYATT, orange, flaked red; FREDERICK SMITH, lilac, striped purple; GEORGE BARNES, pale lilac, striped crimson; HENRY GLASSCOCK, buff, striped crimson; HERCULES, yellow, striped crimson; HUGH AUSTIN, orange-scarlet, striped dark red; JAMES O'BRIEN, yellow, crimson and rose stripes; JESSIE McINTOSH, red, distinct white tips; JOHN FORBES, fawn-colour, striped maroon, fine; JOHN LAMONT, maroon, striped black; LADY ANTROBUS, red, pure white tips; LOTTY ECKFORD, white, striped purple, fine form, new; LUCY FAWCETT, pale yellow, spotted crimson; MADAME SOUBEYRE, rosy-lilac, striped carmine; MANDARIN, yellow, mottled crimson; MISS L. LARGE, puce, striped and spotted with crimson; MONARCH, deep crimson, tipped white; MRS. SAUNDERS, yellow, tipped white, extra fine; ORACLE, deep yellow, striped crimson; PEACOCK, dark maroon, tipped white, large; PROFESSOR FAWCETT, dark lilac, striped chocolate; QUEEN MAB, red, tipped and edged white; R. DEAN, yellow, flaked crimson; REBECCA, lilac, striped crimson, new; REGULARITY, blush-white, striped crimson; REV. J. B. M. CAMM, yellow, flaked red, large; ROBERT BURNS, lilac, flaked dark crimson; SAM BARTLETT, blush, striped crimson; WILLIAM ADY, lilac, striped purple, fine; WIZARD, fawn, striped maroon, tipped white. Bedding and Bouquet or Pompone Varieties. CAMELLIAE-FLORA, pure white, rather large; COMTE VON STERNBERG, yellow, tipped white, small; CRIMSON BEAUTY, maroon-crimson CUPID, white, suffused with rose; DORA, primrose and white, good habit; DOVE, white, tipped rosy-lilac, pretty; E. F. JUNGKER, amber, compact flower; FAIR ELLEN, white, shaded purple; FLORA MACDONALD, pale primrose; GEM, rich scarlet; GEORGE THOMPSON, pure yellow, free; GERMAN FAVOURITE, crimson-lake, deep edge; GOLDEN NUGGET, bright golden-yellow; HEBE, blush, edged rose; JOHN SANDY, buff, tipped red; LADY BLANCHE, pure white, small, fine for cutting; LEAH, yellow, good; LITTLE ARTHUR, bright orange-scarlet; LITTLE BEAUTY, lilac, tipped white; LITTLE DEAR, blush white, tipped rose; LITTLE WONDER, scarlet; MDLLE. VALENTINE FACONET, white and purple, striped; NEMESIS, maroon, tipped white; NORTHERN LIGHT, scarlet, showy; PRINCE OF LILIPUTIANS, deep maroon, very fine; PURE LOVE, pale lilac, extra good; THE PET, dark maroon, white tip; TITANIA, small yellow, free, and good for cutting; TRIUMPH, scarlet; WHITE ASTER, white, free and good. Single Varieties, including a selection from all the various-shaped flowers. ARGUS, deep magenta, shaded rose; B. BARKWAY, deep scarlet, broadly edged orange, new; BEACON, flery-crimson, very fine BEAUTY OF CAMBRIDGE, flery-crimson, fine flower; BEDDING GEM, orange-scarlet, dwarf, very floriferous, new; BRIDAL WREATH, creamy-white; CETYWAYO, rich blackish-maroon, new; CHERRY, bright cherry, shaded rose; CHRISTINE, pale silvery-pink, good; DANGER, glowing scarlet, small flower DARKNESS, intense dark mulberry, distinct; DR. MOFFAT, dark maroon, margined crimson, new FRANCIS FELL, bright rosy-purple; FREEDOM, scarlet-lake, new and fine GEORGE CLARK, deep crimson, edged pale purple, extra fine HARLEQUIN, deep rose, centre band of purple in each petal; H. W. PETITT, bright purplish-rose, edged lilac; IMOGENE, primrose, shaded lilac; LUCY IRELAND, rich magenta, suffused crimson, very fine LUTEA GRANDIFLORA, rich yellow, large and free; MAGPIE, cerise, tipped white, new and distinct, good MAUVE QUEEN, rich mauve, fine large flower; MILLIE GIBBS, white, edged pale yellow, new; MRS. BOWMAN, purple-magenta extra fine, new; MRS. CASTLE, intense lake, a full circular flower, new; MRS. GOLDRING, rich rosy-pink, large flower; NEGRESS, dark maroon, almost black, distinct foliage; NELLIE WARE, purplish-crimson, good form, new; PARAGON, deep maroon, good old variety; SCARLET DEFIANCE, rich scarlet, fine flower; TERRA-COTTA, distinct colour, like terra-cotta; THALIA, rich amaranth, dwarf; T. S. WARE, orange-scarlet, large circular flower, new; UTILITY, orange, suffused scarlet VICTOR STRANDBERG, rich scarlet, dark centre, new; WHITE PET, small flower, white, suffused pale rose, fine for cutting WHITE QUEEN, white, tinged rose, very free; WHITE STAR, white, slightly shaded rose, fine form; WILLIAM CULLINGFORD, rich yellow.
Cactus and Semi-Cactus Varieties, of which D. Juarezii is the type. ANNIE HARVEY, scarlet-crimson, small flowers, very effective, new; COCHINEAL, rich crimson, very fine for cutting, new; CONSTANCE, pure white, free-flowering, most useful; FIRE KING (Glare of the Garden), dazzling scarlet, very floriferous; PARROT, intense orange-scarlet, small, good for cut flowers. DAIS (from dais, a torch; in allusion to the form of the inflorescence). ORD. Thymelaeaceae. A genus containing four species of trees and shrubs, three natives of Madagascar, and one from the Cape of Good Hope. The only one in cultivation is D. cotinifolia, an interesting greenhouse deciduous shrub. It thrives in a mixture of peat and loam. Increased by cuttings, made of half-ripened shoots, or of the roots, in April, placed in sand, under a bell glass, in heat.
D. cotinifolia (Cotinus-leaved). fl. pinkish, in umbellate involucrated heads. June. l. obovate, obtuse. h. 10ft. Cape of Good Hope, 1776. The bark of this yields the strongest fibre known to the natives of Southern Africa.