ABSTRACT
The wild species of Dahlia are natives of Mexico and Central America, where some hybridization and selection had probably already occurred prior to their introduction into Europe at the end of the 18th century. The dahlia can be propagated by seed, tuber, or by stem cuttings from shoots or sprouted tubers. The dormant tubers must be protected from frost in temperate areas. Shoots that arise from tubers are also incompetent, initially, to form flowers when grown in inductive conditions. The tuber, itself, may contribute some inhibitory influence, for cuttings made from these shoots flower earlier, and form fewer leaves than those still attached to the tuber.
