Grown sometimes from seeds, which should be denuded of pulp. Layers of tender branches are sometimes employed. They are most commonly grown from cuttings. These are made from tips of growing or ripened shoots, and are two or three inches long, with all the leaves left on. They are usually, from necessity, variously branched. The soft cuttings are usually taken from forced plants and are handled in a close frame or under a bell-glass, with bottom heat. In commercial establishments the cuttings of ripe wood are preferred. The following is the practice of one of the largest nurseries in the country: Cuttings of the entire season's growth, cut to a heel, are taken in October and November, and are placed in sand in boxes in gentle heat, as in a propagating house. By February the roots will be formed, and the boxes are then placed in a cool house where the temperature is about 50°. Early in spring (about April 1st) the boxes are placed out-doors in cold-frames, where they remain until May, until frost is over. The boxes are then removed from the frames and are set on boards in a shady place, where they are left until fall. In the fall--having been nearly a year in the boxes--the plants are shaken out and are heeled-in in a cellar. The next spring they are planted out in beds, and during the following summer and winter they are given some protection from sun and cold. Yews and arbor-vitæs are handled in the same way. Retinosporas are often grafted upon retinospora or common arbor-vitæ stocks. This operation is usually performed upon potted plants in winter by the veneer method. =Rhamnus=, including Frangula (Buckthorn). _Rhamneæ._ The hardy kinds may be increased by means of seeds or by layers. The stove and greenhouse species may be multiplied by cuttings of growing parts. Seeds should be stratified. =Rhaphidophora.= _Aroideæ._ Increased by seeds; or by cuttings inserted in peaty soil with bottom heat. =Rhaphiolepis= (Indian Hawthorn). _Rosaceæ._ Seeds. Cuttings of firm shoots in a frame. =Rheum= (Rhubarb, Pie-plant, Wine-Plant). _Polygonaceæ._ Increased by seeds and by divisions. Each division should contain at least one bud on the crown. Seeds may be sown where the plants are to stand, but will not reproduce the varieties. =Rhipsalis=, including Lepismium, Pfeiffera. _Cacteæ._ Cuttings, after having been dried for a few days, should be inserted in coarse gravel or sand. See Cactus. =Rhodanthe.= _Compositæ._ Propagated by seeds. =Rhodochiton.= _Scrophularineæ._ Propagated by seeds; and cuttings of the growing wood =Rhododendron=, Azalea (Rose-Bay). _Ericaceæ._