The Garden Under Glass

CHAPTER XXI PROPAGATION UNDER GLASS Seeds and Seed Sowing Under natura! conditions, all the energy of a plant is devoted to the formation and ripening of its seed for the purpose of perpetuating its kind. Hence in a seed we get the concentrated energy of the parent plant, and it is not extraordinary that plants grown from seeds display more vigour and are better able to withstand the vicissitudes of culture than those grown from cuttings. Vigour and strong Constitution, though not always accompanied by delicacy and refinement, either in plants or in human beings, nor necessarily opposed to them, must not be despised. When hybridisers wish to impart vigour to cultivated plants, which by repeated propagation have deteriorated, they invariably cross them with the wild plants whose vigour has remained unimpaired. This has been successfully accomplished with the apple and the potato. Though we get vigour with plants from seeds it is not always possible to use this method of increase ; for there are many plants which do not come true—that is, do not display those useful or beautiful characteristics of the parent that we wish to perpetuate. In such cases recourse must be had to propagation from bud in its many forms of cuttings, layers, roots, runners, offsets, budding and grafting. Colour and fragrance of flowers, form and variegation of leaf and habit of growth are characteristics of a plant which constitute 205