Some species grow well from seed. By young suckers, taken from established plants during summer. Cuttings taken from the axils of the large leaves during early summer push freely, so that they will have plenty of roots before winter sets in. Root-cuttings of _B. cordata_ strike freely. =Bœbera.= _Compositæ._ Increased by cuttings made of young, rather firm shoots, and placed in sand, under a glass. =Bœhmeria.= _Urticaceæ._ Increased by divisions. =Boleum.= _Cruciferæ._ Propagated by seeds sown in a pot in spring, placed in a frame or in the open border during summer. =Boltonia.= _Compositæ._ Increased by divisions of the root in March. =Bomarea.= _Amaryllideæ._ Propagated by seeds, which may be sown in a warm house. Also increased by careful division of the underground stem. In making a division it is necessary to observe that the part taken has some roots by which to live till new ones are formed. =Bombax= (Silk Cotton Tree). _Malvaceæ._ Plants raised from seeds brought from their native habitats make the best trees. Increased by cuttings, which will root readily if not too ripe. They should be taken off at a joint, and placed in sand under a bell-glass, in moist heat. =Bonapartea.= See Tillandsia. =Bonjeania.= See Dorycnium. =Bonnaya.= _Scrophularineæ._ The annual species by seeds, the others by divisions and cuttings. =Bonnetia.= _Ternstrœmiaceæ._ Increased by cuttings of firm, young shoots inserted in sand, under a hand-glass, in a moderate heat. =Borago.= _Boragineæ._ Propagated by seeds sown from spring or autumn in any good garden soil. Also by divisions in spring, or by striking cuttings in a cold-frame. =Borassus.= _Palmæ._ Increased by seeds sown in a strong bottom heat. =Borbonai.= _Leguminosæ._ Propagated by cuttings in spring. They should be half-ripened, and placed in a sandy soil under a bell-glass, in a cool house. =Boronia.= _Rutaceæ._ Increased by seed. By young cuttings, or those made from half-ripened wood. Place these in a thoroughly drained pot of sandy soil, with one inch of sand on the surface, and cover with a bell-glass; remove frequently and wipe dry. =Borreria.= _Rubiaceæ._ Propagated by cuttings. Those of the perennial kinds strike root readily in a light soil, in heat. The annual kinds require a similar treatment to other tender annuals. =Bossiæa.= _Leguminosæ._ Seeds should be sown on a slight hot-bed in March. Also increased by half-ripened cuttings, which should be placed in a pot of sand with a bell-glass over them, in a cool house. =Boswellia= (Olibanum Tree). _Burseraceæ._ Increased easily by cuttings in sand under a glass. =Botrychium.= See Fern. =Botryanthus.= See Muscari. =Bouchea.= _Verbenaceæ._