Desmodium. Leguminosæ.
Increased by seeds, or by cuttings placed under a frame, in heat.
Deutzia. Saxifrageæ.
Commercially, the species are mostly propagated by green hardened cuttings in summer, under a frame. Hard-wooded cuttings may be taken in autumn, and be treated in about the same manner as currant cuttings (see [page 58]). The deutzias are also propagated by divisions and layers. Some of the dwarf sorts are sometimes forced, to make cuttings for winter use.
Dewberry (Rubus Canadensis and vars., and Rubus trivialis.) Rosaceæ.
Seeds are handled in the same manner as blackberry seeds. Increased by layers and, like the blackberry, by root-cuttings. Layers are made by simply covering the decumbent canes at the joints. This is the usual method of multiplication. The tips, too, root freely, as in the black-cap raspberries.
Dianella. Liliaceæ.
Increased by seeds, sown in gentle heat during spring. By divisions.
Dianthera. See [Justicia].
Dianthus. See [Carnation], [Pink] and [Sweet William].