Cuttings
These are portions of a plant, usually the shoots, that are entirely detached, and may, or may not, be used for propagating purposes. A very large number of plants are kept true to character, and rapidly increased, by means of Cuttings. The perpetuation of distinct varieties that may have been obtained from seed, or from fixed sports, is often restricted to the same mode of propagation, as seed from these can seldom be depended on to reproduce the characters of the parent. Certain seasons and selected Cuttings are necessary to insure success with many plants; but with others the season is a matter of little importance, so long as other conditions are suitable. As a rule, these conditions vary very considerably. Cuttings of most soft-wooded plants require a higher temperature, and invariably a much closer atmosphere, than that in which they grow when established, to induce a speedy formation of roots, and, in the meantime, prevent an undue evaporation of moisture. Many hard-wooded exotics also require similar treatment, but in a lesser degree; while others that are hardier, and inserted when the wood is firm and growth inactive, require a longer time to form roots, and consequently a steadier temperature. Soft-wooded plants, to supply Cuttings in spring, should be placed in a little heat, to cause active growth, before they are inserted. Those of firmer growth are best when partially ripened, and side shoots that may be removed with a heel attached are often to be preferred. Roots are formed, in the majority of cases, at the node or joint only, and the incision should be made immediately below. Some plants, however, emit roots at any part of the stem that may be of suitable texture, and these may be cut as shown at Fig. 575. All Cuttings should be selected from healthy plants, and all or the greater part of their leaves retained. It is very important, when inserting, that the base should be placed in contact with the soil; and a layer of sand on the top tends to hold all firmly, until roots are formed. Coniferae, and hardy deciduous trees and shrubs, can generally be propagated by Cuttings. These are best prepared from the terminal shoot of a branch, as represented in Fig. 576, and inserted in early autumn, when growth ceases, and the flow of sap is consequently less rapid. The length and size of Cuttings greatly depend on the variety of plant, those which are of medium growth, neither too sappy nor, on the other hand, too hard, being invariably preferred. Experience will alone teach the proper season, and the most successful method and suitable situation, for propagating by this method in different places, according to the various requirements of the plants to be increased, and the means at command for so doing. Shading, in spring and summer, is necessary in all cases, with tender Cuttings under glass, until they have formed roots.
Leaf Cuttings. Some plants may be increased by the insertion of a leaf with bud attached to the base. In the case of ornamental-leaved Begonias, Gloxinias, and others, young plants are obtained by the formation of bulbs on the petioles and midribs of the leaves, without the presence of an eye or bud. Cotyledons, and some other succulents, may be readily increased from leaves. Root Cuttings refer to roots that ultimately form plants when cut in pieces and inserted in soil. This is a quick mode of propagating such plants as succeed. Clerodendrons and show Pelargoniums, amongst others, may be cited as examples.
For further information on Cuttings, see Propagation.