by Bob Schindler
Air layering produces bigger plants much sooner than rooting cuttings or planting seeds. You do not have to water and check on the plants every day or two. Just air-layer it and forget it!
Before discussing the procedure in air layering, it is useful to compare this technique with other propagation methods.
A Brief Review of Propagation Methods
Plants can be propagated by various means; the table below is a brief overview of the pro and cons.
Method |
Pro |
Con |
Rate of success |
Seeds |
Inexpensive. |
Seedling not an exact copy of parent. |
Very good |
Cuttings |
Inexpensive. |
Time consuming; must monitor cuttings. |
Good |
Air-layering |
Inexpensive. |
Need repeat visit to the original plant. |
Very good |
Grafting |
Inexpensive. |
Requires more know-how. |
Low for novice |
Tissue culture |
Many plants in short time. |
High investment cost. |
??? |
A Bit of Botany
Between the bark (phloem) and the wood (xylem) is a very thin layer called ‘cambium’. This layer is 1-3 cells thick and in this area is all the action regarding growth of a plant. In the cambium area are undifferentiated cells that can become bark or wood, or roots if the stem is wounded as in air-layering.
Air Layering
The following is modified from an article by the American Camellia Society.
Air layering is an easy and effective way to produce fairly large plants in a single season. The process usually begins in the spring and ends in the fall. In Georgia, we begin in March and can cut off the layered limb in August. Unlike normal layering where a low limb is layered in the ground, this method roots plants in the air.
On a healthy limb, completely remove a ring of bark 1 1/2 to 2 times the diameter of the branch to be air layered. This should be 12 - 24 inches from the tip of the limb. To remove the bark and cambium, the easiest way is to use an ordinary pair of pliers, but you can carefully use a knife. Grasp the branch with the pliers and rotate the pliers around the branch, removing the branch's bark. Alternatively, two parallel cuts may be made with sharp clippers or a knife and the strip lifted off. The branch may be producing new growth, however, the girdled wood must already be hardened off.
Remove all traces of the cambium layer (green tissue just inside the bark) by scraping with a knife or the pliers. If the bark is slipping, scraping will not be necessary as the cambium layer will be removed with the bark. Dust the exposed surface with a rooting hormone powder recommended for hardwood cuttings or brush on with a paintbrush if it is a liquid solution. Most roots will grow from the upper (outer) end of the bare area, so be sure to put rooting hormone in this area.
Squeeze excess water from a handful of moistened sphagnum moss and place it in the center of a rectangular piece of aluminum foil about 6 by 8 inches in size. Press a narrow trough by hand into the moss. Then place the moss around the branch of the plant with the trough around the branch. Wrap this tightly with the aluminum foil, dull side out to discourage birds from pecking. Twist the ends of the foil around the limb. Use a double layer of foil or heavy-duty foil, if you prefer.
Make a log sheet to maintain a record of all your air layered plants. Provide for each plant a number, location, description/plant name, and room for a comment. Take a piece of flagging tape, clearly write the number on the tape with a permanent marker, and tie to the air-layered branch.
Air layers started in the spring will usually formed roots by late summer. When the roots are visible through the moss (they are usually white), cut the limb from the mother plant at the bottom edge of the moss with sharp pruners. If roots did not develop satisfactorily, just leave the branch on the plant.
Do not try to remove the sphagnum moss; you may damage the roots. Soak in a bucket of water before planting. Best results will usually be obtained by planting first in a container, although it can go directly into the ground in a well-prepared hole. Air layers will often flower the first year, but remove excessive buds to allow the plant to concentrate on root growth.
Fill out the comment section of the log sheet with how successful each layering was. Keeping good records will help you become a better propagator.
Material Required for Air-Layering
- Sphagnum Moss
- Bucket with Water
- Aluminum Foil
- Rooting Hormones, 0.1, 0.2, 0.8%
(use depending on type of plant) - Kitchen knife and/or pliers
- Marking tape and Marking Pen
Some Plants To Try Air-Layering
Common Plant Name |
Bot. name |
How many |
Success rate |
Azalea, evergreen |
Rh. species |
some |
Good |
Azaleas, native |
Rh. ?? |
Just a few |
??? |
Banana shrub |
Michelia figo |
some |
?? |
Beech, American |
Fagus grandiflora |
many |
??? |
Cleyera japonica |
Temstroemia gymnanthera |
some |
??? |
Crape myrtle |
Lagerstroemia indica |
many |
Good |
Deodar Cedar |
Cedar deodara |
many |
Very good |
Doublefile Viburnum |
Viburnum plicatum |
lots |
Very good |
Eastern Red cedar ‘Gray owl |
Juniperus virginiana |
many |
Very good |
Forsythia |
forsythia |
many |
Very good |
Fragrant Tea Olive |
Osmanthus fragrans |
some |
Good |
Gardenia |
Gardenia jasminoides |
many |
Good |
Hemlock |
Tsuga canandensis |
many |
?? |
Hornbeam, American |
Carpinus caroliniana |
some |
??? |
Japanese Camellia |
Camellia japonica |
many |
Very good |
Japanese maple |
Acer palmatum |
many |
Good |
Korean spice Viburnum |
Viburnum carlesii |
many |
Very good |
Lady banks’ rose |
Rosa banksia |
many |
Good |
Loropetalum |
Loropetalum chinense |
many |
Good |
Magnolia ‘Bracken’s Brown Beauty’ |
Magnolia grandiflora |
A few |
So-so |
Maple-leaf Viburnum |
Viburnum acerifolum |
many |
Very good |
Redbud |
Cercis canadense |
A few |
???? |
Rhododendron, various |
Rhododendron hybrids |
some |
Good |
River birch |
Betula nigra |
some |
Good |
Sasanqua Camellia |
Camellia sasanqua |
lots |
Very good |
Washington Hawthorn |
Crataegus phaenopyrum |
lots |
???? |
Loebner Magnolia |
Magnolia X loebneri |
1-2 |
???? |