Propagation of Evergreen Azaleas
R. D. Welshmer, Birmingham, Alabama
The best method of propagating evergreen azaleas is by green wood cuttings. Many cuttings can be taken from a plant and they will all be exactly like the parent.
Prepare a cold frame with a mixture of half sand and half sphagnum moss, well mixed and well watered. Cuttings should be taken in July but I have taken them as late as Labor Day. Ideally, the cuttings should be three to four inches long. Sometimes, especially with dwarf varieties, it is impossible to find them that long; shorter ones may be used if the watering is checked carefully. The new growth should be crisp enough to snap off the parent plant like snapping a green bean. If the cuttings will not snap they are not hard enough; wait a few more weeks.
Remove all leaves except four or five at the top. Some people like to pinch out the terminal buds to promote branching; I like to see the plants bloom, verify their identity, and then pinch them back. I still get bushy plants. Dip the stems of the cuttings in Rootone F and plant in the cold frame two to three inches deep and just far enough apart so that the tops of the cuttings do not touch each other, about one-half inch. Then water the cold frame and cover the top with plastic. If the frame is not in a semi-shaded area, place laths across the top.
Open the frame from time to time, even during cold weather, and water if it needs moisture. If any physical problems occur inside the frame, such as insect damage or fungus, treat them chemically as you would any other plants, being careful not to over-treat.
Leave the plants in the frame until May. They should have formed healthy root masses by then. Separate them and move them to a nursery bed of good soil mixed with sphagnum peat, well watered. They will need to be checked regularly and watered when dry the first summer. They may be fertilized lightly with an azalea fertilizer in June and July, but not after July 15. Their growth needs to slow down in order to harden them for winter.
If you want only a plant or two use an inverted glass jar to cover the cuttings; place it well back in the shade of the parent plant. Plant the cuttings in the mulch that covers the ground.
Azaleas can also be propagated by layering. Bend down a branch of a mature plant. Where it touches the ground scrape off a bit of the outer bark down to the green cambium layer; do not cut into it; cover this scraped part with the mulch which is on the ground and secure it with a long forked stick or wire. Leave attached to the parent for a year before transplanting.
Air layering is a method that can be used to make a small new bush plant from a leggy branch of an old plant. Prepare the upright branch in the way described in the last paragraph. Then wrap a double handful of well soaked sphagnum around the scraped area; wrap this tightly with plastic and tie well to make an air-tight bundle. Keep constantly moist until a good root ball has formed and it can be cut loose and planted: about a year.
If you should catch azalea fever as I have and want to repeat, be sure to change the medium in the cold frame each year.