Page:Encyclopædia Britannica, Ninth Edition, v. 12.djvu/250

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238 HORTICULTURE [PROPAGATION the leaf, and should have all underground buds carefully removed so as to prevent as far as possible the formation of suckers. These cuttings should be about one foot in length, and should be planted at once in the ground so as to leave only the top with the two or three preserved buds exposed. If a clean stem, however, is desired, a longer portion may be left uncovered. Cuttings of growing plants are prepared by removing with a sharp knife, and moderately close, the few leaves which would otherwise be buried in the soil ; they are then cut clean across just below a joint ; the fewer the leaves thus removed, however, the better, as if kept from being exhausted they help to supply the organizable matter out of which the roots are formed. Free-rooting subjects strike in any lightish sandy mixture ; but difficult subjects should have thoroughly well-drained pots, a portion of the soil proper for the particular plants made very sandy, and a surfacing of clean sharp silver sand about as deep as the length of the cutting (fig. 60, c). Mr Ayres, writing in the Gardeners Chronicle (1843, p. 116), recom mends 5-inch pots for cuttings ; and these he prepares by placing over the hole at the bottom of each an inverted 3-inch pot, around it potsherds broken small, over these some moss, and then the compost made up of equal quantities of peat, sand, and leaf-mould, leaving about half an inch at top for white sand, which runs into the holes as the cuttings are inserted. Mr Ayres advises that a stock of pots thus prepared should be kept in a frame or propagating house, as nothing is so injurious to cut tings taken from plants growing in heat as to put them into cold soil. Cuttings cannot be too short if they have the necessary buds to form a plant ; neither can they be inserted too shallow, if they are made firm in the pots." Fl - 61. Double Cutting Pot. All plants while striking may be kept in a temperature rather higher than that in which they grow naturally, and the soil about them should be kept moist, although they must not from want of drainage in any degree get sodden with wet. The humidity kept up about the cuttings is maintained by covering them with bell-glasses, or setting them in handliglits or small glazed frames of convenient size. A special contrivance for a cutting pot (fig. 61) was brought into notice many years ago by Mr A. Forsyth. A smaller pot was put into a larger one, the hole at the bottom being closed with clay a ; the bottom of the outer pot is filled with crocks b, so that the small pot is brought up to the level of the larger one ; and the space between the two pots c is filled with propagating soil, the cuttings being so planted that their ends rest against the sides of the inner pot, which is then filled with water, and this passing slowly through the sides of the pots, just keeps the soil moistened. L.6 FIG. 62. Leaf Cuttings. Such delicate plants as heaths are reared in silver sand, a stra tum of which is placed over the sandy peat soil in the cutting pot, and thus the cuttings, though rooting in the sand, find at once on the emission of roots congenial soil for them to grow in (fig. 60, c). Hardy plants, such as pinks, pansies, &c., are propagated by cut tings planted during early summer in light rich soil. The cuttings of pinks are called pipings (tig. 60, d), and are planted about June, while pansies may be renewed in this way both in spring and in autumn. (13) By Leaf Cuttings. Many plants may be propagated by Leaf planting their leaves or portions of their leaves as cuttings, as, for cuttings, example, the herbaceous Gloxinia (fig. 62, a) and Gcsnera, the suceiilent Scmpcrvivum, Echeveria, Pachyphytum, and their allies, and such hard-leaved plants as Thcophrasta (fig. 62, b}. The leaves are best taken off with the base whole, and should be planted in well-drained sandy soil ; in due time they form roots, and ultimately from some latent bud a little shoot which forms the young plant. The treatment is precisely like that of branch cut tings. Gloxinias, begonias, &c. , grow readily from fragments of Fj 63. -Leaf Propagation. the leaves cut clean through the thick veins and ribs, and planted edgewise like cuttings. This class of subjects may also be fixed flat on the surface of the cutting pot, by means of little pegs or hooks, the main ribs being cut across at intervals, and from these points roots, and eventually young tubers, will be produced (fig. 63). (14) By JRoot Cuttings. Some plants which are not easily increased Root by other means propagate readily from root cuttings. Amongst the cuttings indoor plants which may be so treated, the Bouvardia, Pelargonium, Aralia, and Wigandia may be mentioned. The modus op crandi is to turn the plant out of its pot, shake away the soil so as to free the roots, and then select as many pieces of the stouter roots as may be required. These are cut up into half-inch lengths (some times less), and inserted in light sandy soil round the margin of a cutting pot, so that the upper end of the root cutting may be level with the soil or only just covered by it. The pots should be watered so as to settle the soil, and be placed in the close atmosphere of the propagating pit or frame, where they will need scarcely any water until the buds are seen pushing through the surface. There are various herbaceous plants which may be similarly treated,, such as sea-kale and horseradish, and, among ornamental plants, the beautiful autumn-blooming Anemone japonica and Senccio pulelt,er. The sea-kale and horseradish require to be treated in the open garden, where the cut portions should be planted in lines in well-worked soil ; but the roots of the Anemone and Senccio should be planted in pots and kept in a close frame with a little warmth till the young shoots have started. Various hardy or namental trees are also increased in this way, as the quince, elm, ro- binia, and mul berry, and the rose amongst shrubs. The most important use to which this mode of propagation is put is, however, the increase of roses, and of the various plums used, as stocks for work ing the choicer _ stone fruits. The method in the latter case is to select roots averaging the thickness of the little finger, to cut these into lengths of about 3 or 4 FIG. 64. Cutting of Single Eye. inches, and to plant them in lines just beneath the surface in nursery beds. The root cuttings of rose-stocks are prepared and treated in a similar way. (15) By Cuttings of Single Eyes. This mode of propagation is Eye performed by cutting the branches into short lengths, each containing cuttings one well-matured bud or eye, with a short portion of the stem above.

and below. It is a common mode of propagating vines, the eyes