Seeding is the most common way that flowering plants use to reproduce in nature. It is normally a sexual method and by this there is always a possibility of a variety of genetic combination, variation that provides the basis by which plants adapt to their environment and enables the breeding and selection of cultivars.
This is a natural form of propagation. Roots are induces to develop by covering a stem with soil while it is still attached to the parent plant. The rooted portion of the stem is then separated from the parent plant and grown on. In order to help the stem to promote root growth, this is often cut, ring-barked or twisted. Also for further stimulation of rooting you can use a rooting hormone at the point of layering.
Propagation by cuttings is the most common vegetative method. There are three main types of cuttings: stem, leaf and root. Stem cuttings produce roots directly from the stem itself, large leaves used as cutting material will develop roots from near their veins and roots cuttings will produce both adventitious stem buds and roots.
Storage organs have diverse structures and include: bulbs, corms, rhizomes, root and stem tubers, and turions. In nature most plants with storage organs will produce offsets. These you can lift and divide to prevent overcrowding. Apart from division you can propagate these plants by cutting the storage organs into sections and stimulate them to produce offsets by wounding.
Grafting and budding
For many woody plants and few herbaceous ones, a budded stem or scion is grafted onto a rootstock or stock of another species or cultivar to achieve a composite plant with more desirable characteristics. Sometime this method is used because the stock may be more resistant than the scion to root disease or more suited to a particular environment.