Corydalis. Fumarieæ.
Increased by seeds, or by dividing the plants directly after flowering. The bulbous-rooted species by offsets.
Corylus (Hazel; Cob-nut). Cupuliferæ.
Propagated by seeds, suckers, layers or cuttings. Grafting and budding are each practicable, and are adopted when growing tall standards or scarce varieties. The seed of all should be sown as soon as gathered, or stored in sand till the following spring. All superior varieties should be increased by suckers or layers. Stools kept for layering must be allowed to make more growth than those used for suckers. Free growth must be encouraged for a year or more, and, any suitable time in winter, the shoots should be bent to the ground, pegged firmly, and covered to the depth of three inches with earth. They will be well-rooted by the following autumn, and may then be removed and planted out permanently.
Corynostylis, Calyptrion. Violarieæ.
Increased by seeds, or by cuttings of the young wood, placed in sand in bottom heat, under glass.
Cosmos. Compositæ.
Seeds, usually started under glass. The tuberiferous species, like Dahlia, which see.
Costus. Scitamineæ.
Increased by dividing the roots.