=Cuphea.= _Lythrarieæ._ Increased easily by seed; but cuttings of the perennial sorts strike freely in March or April, in brisk bottom heat. =Cupressus= (Cypress). _Coniferæ._ Seeds may be collected in early spring, and should be sown in April in a warm, friable soil. Cuttings of growing or mature wood, much as for Retinospora, which see. =Curculigo.= _Amaryllideæ._ Seeds; also by suckers, which form at the base of the stem. =Curcuma= (Tumeric). _Scitamineæ._ Increased by root division. =Currant= (_Ribes rubrum_, _R. nigrum_ and _R. aureum_). _Saxifrageæ._ New varieties are grown from seeds, which may be sown in the fall or stratified until spring. Varieties are nearly always multiplied by hard-wood cuttings (Fig. 49). The cuttings may be taken in spring and placed directly in the ground, but better results are obtained by taking them in the fall or late summer. Many nurserymen prefer to take them in August, strip off the leaves, and bury them in bunches with the butts up. They may remain in this condition or in a cellar all winter, or they may be planted in the fall. Currant cuttings strike readily, however, under any method. Some growers cut out the buds which come below the surface of the ground to prevent suckering, but this is not generally practiced; the suckers are cut off when the cuttings are removed from the cutting bed, either to be sold or to be transplanted into nursery rows. Green-layering is sometimes practiced with rare sorts, or single eyes may be used, as in grapes. Tip-layering, as in the black raspberry, may also be employed. (See page 33.) Weak or low sorts are sometimes grafted upon stronger ones, in order to give them a tree form, but such bushes are grown only as curiosities or as specimen plants. =Cussonia.= _Araliaceæ._ Increased by cuttings, which should be planted in sand, under glass. Give slight bottom heat. =Custard Apple.= See Anona. =Cyananthus.= _Campanulaceæ._ Seeds. Strong roots may be carefully divided in spring, but this is not desirable. Usually by cuttings, which should be taken during spring or early summer, and struck in sandy peat, being kept moist. =Cyanophyllum.= _Melastomaceæ._ Increased by seed. By cuttings or eyes, which should be placed in sand where a good bottom heat must be maintained, and they should be shaded from the sun. =Cyanotis.= _Commelinaceæ._ Seeds; usually by young cuttings in sandy soil, in brisk heat. =Cycas.= _Cycadaceæ._ Increased by seed, and oftener by suckers. =Cyathea.= See Ferns. =Cyclamen= (Sowbread). _Primulaceæ._ Propagated by seed, sown when freshly gathered; the hardy kinds in pots placed in a cool frame. By divisions and leaf cuttings, taken off with a heel; but these methods are not very satisfactory. =Cynoglossum.= _Boragineæ._