Seeds. Cuttings may be made in summer, and placed under a frame in a shady situation.
Delphinium (Larkspur). Ranunculaceæ.
Seeds may be sown out-doors in a warm border in spring, or in pans, to be placed either in frames or outside. The old plants of perennial sorts may be cut down after flowering, when young growths will proceed from the base, and the whole may be lifted and carefully divided. Cuttings of the young shoots, taken in autumn or spring, will root freely if potted singly and placed in a cold-frame. They will flower the following season at the same time as the divisions.
Dendrobium. Orchideæ.
The methods of propagating these plants have already been mentioned. Where a rapid increase of a new or special variety is required, the pseudo-bulbs that are more than one year old should be cut into lengths, and fastened on orchid rafts, with a layer of sphagnum beneath them. Suspend them in a hot, moist house, if possible, over a water-tank. The advantage of this method is that the young plants do not need shifting after they commence rooting on their own account. The section to which D. aggregatum, D. Jenkinsii, D. densiflorum and D. thyrsiflorum belong, are best propagated by division. (See under [Orchids].)
Dentaria (Toothwort). Cruciferæ.
Propagated by seeds or divisions.
Deodar. See [Cedrus].
Desfontainea. Loganiaceæ.
Cuttings, placed in a sandy loam, in a gentle heat.