Anybody can do it! All it takes is a little bit of special plastic film called Polyethylene, a sharp knife, some moist sphagnum moss, and a little rooting powder.
With these materials, any gardener can propagate new shrubs and trees without using a hotbed.
New Polyethylene Film Experimentation
John Creech of the United States Department of Agriculture has experimented with this new Polyethylene film for over 2 years with excellent results.
At the Arnold Arboretum, we started using the film in the summer of 1949 and have been surprised at the ease with which woody plants can be propagated.
The new Polyethylene film allows the transfer of gases but not water vapor.
As a result (providing the film is tied securely), the moist sphagnum moss will remain moist for months or even a year.
Made by the Du Pont Company, it is used for packaging fruits and vegetables since it is transparent.
It keeps the contents in good condition for a great length of time if unavailable locally. However, it may be secured from Airwrap Products, Laurel, Florida, at $1.50 for a one-pound roll.
Steps In Air-Layering
The steps in air-layering are simple:
In late spring, select a shoot of last year’s wood, or in June or early July, a shoot of the current year’s wood about the size of a lead pencil or larger.
A longitudinal cut is made carefully and cleanly for a distance of 3” to 3 ½” inches down the middle of the stem without seriously breaking the twig.
(It must remain attached to the tree or shrub until roots have formed.)
The cut surfaces are dusted with a rooting hormone powder. A handful of wet sphagnum moss is squeezed to remove excess water, but it should still be moist.
Some moss is then packed between the cut surfaces so these will not grow together, and the rest is packed in a ball completely around the twig so that the whole area in which the cut is made is completely surrounded by moist moss.
Then a piece of Polyethylene film, possibly 10” x 10” inches, is tightly wrapped around the moss to hold it securely in place.
It is tied top and bottom, the top end being turned down to shed water and not funnel it into the wrapping inside.
On some plants, the ball of moss may be a rather heavy burden on the supporting stem, so it may have to be staked or tied to some support.
The best time to cut the rooted twig from the plant is when the leaves have dropped, and the plant is in a dormant condition.
Because of their delicate nature, it might be well to pot such rooted twigs and keep them in a protected place over the first winter.
Certainly, by the following spring, after all, the danger of frost is over. They can be set in good soil in a protected place where the ground will not dry out.
This is all there is to the process. Experienced plant propagators who are now using the new film are enthusiastic about it and trying it on many things considered difficult to root.
It affords an easy and effective way for the home gardener can propagate his favorite trees and shrubs.
Four Steps In Cutting
Here are the four steps in cutting:
- A cut is made in a young shoot down the middle of the stem and held open with a ball of sphagnum moss. Cut surfaces are then dusted with rooting hormone.
- Moist sphagnum moss is packed into the cut and all around the outside. Ensure the cut surfaces are spread apart to prevent them from growing together again.
- After the moss is packed around the cut, it is completely covered with Polyethylene film and left to root. The film will keep sphagnum moss moist for months.
- This crabapple, variety Dorothea, was rooted in three months last summer. Many hard-to-root trees and shrubs have been propagated using this film.
44659 by Donald Wyman