Layering

Natural layering typically occurs when a branch touches the ground, whereupon it produces adventitious roots.

The horticultural layering process typically involves wounding the target region to expose the inner stem and optionally applying rooting compounds.

In ring air layering, the exposed wound is covered in a growth medium such as sphagnum moss, and wrapped in a material such as plastic.

[2] Layering is more complicated than taking cuttings, but has the advantage that the propagated portion continues to receive water and nutrients from the parent plant while it is forming roots.

A low-growing stem is bent down to touch a hole dug in the ground, then pinned in place using something shaped like a clothes hanger hook and covered over with soil.

The resultant notch should be wedged open with a toothpick or similar piece of wood and the hormone applied before burying.

[6] Ground layering or mound layering is the typical propagation technique for the popular Malling-Merton series of clonal apple root stocks, in which the original plants are set in the ground with the stem nearly horizontal, which forces side buds to grow upward.

In air layering (or marcotting), the target region is wounded by an upward 4 cm long cut and held open with a toothpick or similar, or a strip of bark is removed.