Air layering is a means of propagation whereby a part of a woody plant is induced to develop roots by wounding the stem of the plant and enclosing it in moist moss. In a matter of weeks or months, depending on the plant, roots will form from the cut area. When the roots are well developed the new plant is removed from the parent plant by cutting off just below the roots and potting it separately.

PROCEDURE FOR AIR LAYERING

For optimum rooting make air layers in the spring on shoots produced during the previous season or in mid-summer on mature shoots from the current season's growth. On woody plants, stems of pencil size or larger are best. The stem may be much thicker on the more herbaceous plants.

1) With a sharp knife, make two parallel cuts about 1 1/2" apart around the stem and through the bark and cambium layer. Connect the two parallel cuts with one long cut and remove the ring of bark leaving the inner woody tissue exposed.

2) Apply a rooting hormone such as Rootone® F to the wound then apply a handful of damp sphagnum moss so that it surrounds the wounded portion of the stem. Tying the moss in place with string helps keep it in position while completing the process. The sphagnum moss should be soaked several hours to insure that it is thoroughly moist. Wring out excess water before using as too much moisture will cause decay and deterioration of the plant tissue.

3) Wrap clear plastic such as Saran Wrap or sandwich bag type plastic around the sphagnum moss several times and secure it (wrap it) with electricians tape at the top and at the bottom. This seal should be such that excess water can escape but moisture will be retained.

4) After the new roots have penetrated the moss ball and are visible on all sides (this may take anywhere from a few weeks to several months), remove the newly rooted plant from the parent plant with a sharp knife or pruning shears, making the cut just below the ball of moss and roots. 

5) Carefully remove the plastic without disturbing the roots or removing the ball of moss and plant in a container using a good potting mixture or plant in a well-prepared soil bed.

Sources: Plant Propagation by Layering: Instructions for the Home Gardener 1/99 HIL-8701, Erv Evans, Extension Associate Frank A. Blazich, Professor Department of Horticultural Science, NC State University; Air Layering for Difficult-to-Root Plants, Everett E. Janne, Extension landscape horticulturist, Texas Agricultural Extension Service