Cytisus (Scotch Broom). Leguminosæ.
By seeds and layers. In spring, cuttings of young wood may be taken when about three inches long (with a heel preferred), placed under a bell-glass in heat, or in a close frame, where they will root readily. If gradually hardened, potted and grown on, small flowering specimens may by obtained the following spring. C. purpurea is usually grafted on the common laburnum.
Dacrydium (Tear Tree). Coniferæ.
Increased by fresh seed and ripened cuttings.
Daffodil. See [Narcissus].
Dahlia. Compositæ.
Single varieties, and sometimes the doubles, are grown from seeds. The roots may be broken apart after the crowns have started in spring, and each part grown separately. The roots may be started into growth in heat late in winter, and the young sprouts may be removed and handled as ordinary cuttings as fast as they form. Or rare sorts may be increased during summer by cuttings from the growing tips. Cions made of the growing tips may be grafted into the roots by a cleft or side graft. This method is oftenest employed for the purpose of preserving over winter rare sorts which it is feared may be lost. The grafts are kept growing slowly during winter, and cuttings may be taken from them. Cuttings should always have a bud or buds at the base, and in propagation by division there must be a piece of the crown attached to the root.
Daisy. See [Bellis].
Dalbergia. Leguminosæ.