Over the past thirty years, I have sought to develop a
reliable process for propagating native azaleas. For the first twenty of those
years, my efforts were met with little or no success. The next five years showed marked improvement, and for the
last five years I have been consistently rooting at the rate of eighty percent.
After much trial and effort, I have learned that some plants simply will not
root. Ironically, these are usually the very best plants. Although this may seem
frustrating, do not give up. For instance, I dug a 'horizontal calendulaceum' in
1963 and for twenty-eight years it refused to root. After all that time, last
year it produced two plants, and from those two plants, four were yielded this
North Georgia contains a variety of native azalea species
that have crossed naturally through the years to form natural hybrids or
inter-species hybrid azaleas. This natural crossing may serve to aid the
propagation process. While I have been successful in propagating particular
plants in all species, I have also found individual plants that will not root in
each of the species I have worked with. For years I have been told that you
can't root native azaleas, but I have been quite pleased with the results. The
following sections provide a detailed methodology I have developed over the
years for propagating native azaleas.
The bench measures four feet wide, eight feet long, and
twelve inches deep. On the bottom of the bench is a one-fourth inch hardware
cloth topped by a three-fourth inch water pipe. Next is three inches of large
pine bark, a heating cable or hot water pipe, and three inches of small pine
Four daylight tubes, eight feet in length, are positioned
two feet above the propagating bench. These tubes are controlled by a
twenty-four hour clock with one hour trips (on at 7:00 PM, off at 11:00 PM).
Primary Mist System
The primary mist system consists of a filter, solenoid
valves, and a twenty-four-hour clock with fifteen-minute trips that controls a
six-minute clock with one-second trips. Flora Mist brand nozzles are used in
conjunction with baffle wire and placed eighteen inches above the bench. The
mist head spacing is not to exceed three feet six inches, and the operating
pressure on these heads should be set to sixty psi. This system should be
operated from 8:00 AM to 7:00 PM for two seconds every two minutes or for one
second every one minute. By the first of July the primary mist system is phased
out to allow the secondary mist system to take over.
Secondary Mist System
I use a Mist-A-Matic brand system made to operate around
the clock. Although this system is billed to operate twenty-four hours a day, in
actuality it operates from 7:00 PM to 8:00 AM or as needed.
The medium consists of two parts pine bark (screened
through a one-fourth inch screen), one part peat moss and one part Perlite. It
should be subjected to the mist for a period of seven days before it is ready to
accommodate the cuttings.
Use tree seedling pots measuring 3" x 3" x 5 1/2" with an 'almost open' bottom.
The recommended hormones are Hormodin #3 and Roots, a
liquid gel (Canadian product). Failure to use a hormone in the propagation
process slightly lowers the success rate percentage, but if the cutting roots
they will break into new growth sooner without the added hormones.
The fertilizer of choice is Peters 21-7-7 distributed in a
Gewa injector with a 1-100 mixing valve. Issue the fertilizer at a ratio of two
pounds per gallon (derived from the Gewa Constant Feeding Chart for a seven to
ten day feeding). If watering by hand, mix one teaspoon of fertilizer per gallon. Plants should be
fertilized beginning on the fifteenth day of June and every ten days thereafter.
Moreover, make sure never to fertilize plants that are in winter dormancy.
Cuttings from the Garden
Here in Georgia I generally take cuttings from the 1st of May to
the 20th of May but never after May 30th.
The cutting should be taken “very early” in the season while it is
“extremely soft” from a plant that has been well watered and fertilized with
a well balanced mix the previous year. The plants also need to be in a stage of
active growth. After taking the cuttings, put them in a plastic bag and place
them in a refrigerator for twelve to forty-eight hours. It is very important
that water not be added to the plastic bag prior to refrigeration.
Cuttings from the Mountain
If the cuttings are allowed to wilt, they will not root.
Therefore, the cutting should be taken early in the morning, placed in an
airtight plastic bag with a wet paper towel, and if at all possible, stored in a
cooler with ice. The cooler will greatly increase the probability of successful
propagation. I have even converted
a backpack into a small cooler for this very purpose.
After removing the cutting from the refrigerator, remove
the tip and all but four leaves. Next, cut off one-half of each of the remaining
four leaves and dip the cutting into a Insecticide - Fungicide mix before placing it
into the medium. By July the cutting will begin to show new growth, and by the
first of October it will have grown an additional six to eight inches in length. In the middle of October, move the
rooted cuttings to a cold frame covered with white polyethylene for the winter
The greenhouse should receive a full measure of sunlight
from 8:30 AM to 7:00 PM, and no shade should be provided for the propagating
bench. The temperature rises to a full 100 degrees Fahrenheit in the greenhouse
while the medium temperature approached 85 degrees Fahrenheit under the mist.
Experience has proven that providing this atmosphere to the cuttings increases
the likelihood of success.
The rooted cutting should not be potted up until the
Conventional wisdom discourages the possibility of
propagating native azaleas, but the formula I have developed after years of
trial and effort has consistently provided a respectable level of success. While
each of the steps involved in the process is important, there are three areas
that require the most attention: the timing of taking cuttings, using the
refrigerator, and fertilizing properly. Giving these three steps the utmost
attention will greatly increase your chances of success.