Propagation has always been something that interested me. As soon as I learned that there were simple methods for turning the one plant I already loved into two, three, or more, I was hooked. There are many ways of propagating plants, and the type of plant you are trying to reproduce will determine the approach you should use. When it comes to Azaleas, air layering is one of the easiest and best methods.
Air layering is accomplished by cutting into a branch of an existing Azalea and wrapping the damaged area in moist sphagnum or coir. Roots grow from the wound over the next few weeks or months. Then when there is a nice root ball, the branch is cut off and planted into the ground. And voila! You now have a brand new, genetically identical shrub.
While air layering isn’t possible with all types of plants, it works well with Azaleas. And though not all propagation methods are easy for beginners, air layering is. This guide includes everything you need to know and step-by-step instructions for air layering your beloved Azaleas.
What is Air Layering?
Air layering is one of the easiest ways to get new Azalea plants because it allows you to start with a healthy portion of your mature plant and grow a new root system while the mature plant is still safely planted in the ground.
This is accomplished by scraping back the bark around a healthy branch, scoring the wood, and wrapping it in a moist growing medium. After a few weeks or months, the plant will start to produce new roots at this point in the branch.
There are lots of ways to propagate plants, but air layering is one of the simplest for home gardeners to do. Once the plant has developed a new root system at the scored location, you simply cut just underneath and plant the newly rooted section on its own.
Why Choose Air Layering for Propagating Azaleas
Air layering is a “set it and forget it” method of clonal propagation that works well with Azaleas and has a high success rate for beginners. It doesn’t take a lot of your time, and it isn’t expensive. In fact, you probably already have everything you need to air layer your Azalea shrubs.
Another reason to air layer is that it yields big plants quickly. New air layers are around a foot tall and can flower their first year. You also get an exact genetic copy of the parent plant.
One word of caution – air layering works best with evergreen Azaleas. If you have deciduous Azaleas, you can definitely try air layering, but the success rate is lower. (Not sure if your Azaleas are evergreen or deciduous? Check out this post.)
How to Air Layer Your Azalea
If you’ve decided you want to try your hand at air layering, I’m going to break it down very simply for you. Below are the step-by-step instructions for propagating your Azalea via air layering.
Materials and Tools
You will need:
- A sharp knife or pruners to cut the branch
- Pliers (optional but helpful)
- A rooting medium like sphagnum moss or coconut coir
- A bucket with water to moisten the rooting medium
- Plastic (such as plastic wrap or a cut-up trash bag) or aluminum foil to wrap around the branch and rooting medium
- Something to secure the plastic with, such as string, tape, twist ties, zip ties, or floral wire
- Optional: rooting hormone
- Optional: rooting pod clamshells (I use these instead of plastic wrap or aluminum foil)
Another option is to buy an air layering kit.
How to Choose a Branch for Air Layering
The first step is to choose a branch that will become your new Azalea. You’ll be cutting this branch off of the parent plant, so choose one that the plant can comfortably spare, and that won’t leave it looking awkward.
You should select a healthy branch, at least a foot long and about the thickness of a pencil. It can have new growth on it, but the place you cut should not be brand new growth.
Identify a spot one to two feet from the tip of the branch where you will make the wound. Everything above this will be your new plant. For best results, choose a place where you can score just below a node. Nodes are the areas along the branches and stems where new growth, leaves, and flowers emerge. These are also the sections that have the tissue needed to produce roots. To locate a node, find a section just below where there is a split, and one branch splits into two.
Starting the Layer
Step 1: Soak the Rooting Medium
The sphagnum moss or coir needs to be thoroughly moist when you apply it. Soak it in water while you do these other steps.
Step 2: Prepare the Branch
Trim off the leaves and twigs around the section you’re going to work with. You’ll want about six inches of clean branch.
Step 3: Strip the Branch
Grip the branch in your pliers and rotate them back and forth around the branch to remove the bark. You may need to scrape off the cambium layer (a thin layer between the bark and the woody center of the branch) with your thumbnail or a knife if it doesn’t come off with the bark. You should strip a one-inch section of the branch.
Alternatively, use a knife or clippers to make a shallow cut and score all the way around the branch. Then make a second cut about an inch away and use the knife to carefully scrape away the bark and cambium between the two cuts.
There is another method of air layering that involves making a deep cut instead of stripping the bark, but that method isn’t always recommended for Azaleas.
Step 4: Optional – Apply Rooting Hormone
You don’t need rooting hormone for air layering to work, but it can be helpful. Rooting hormone comes in liquid and powder forms. If you have rooting hormone, brush or sprinkle it over the entire stripped area.
Step 5: Cover with Rooting Medium & Secure in Place
Scoop up a large handful of moistened sphagnum or coir, squeeze out any excess moisture, and cover the stripped section of the branch with it. Be sure that there is a thick enough covering for the roots to grow into. Wrap the plastic, aluminum foil, or a clamshell around the branch and secure it above and below the rooting medium, either with your ties or by wrapping the foil tightly, creating a bundle around the branch. You may need a couple of layers of plastic or foil to hold the rooting medium securely in place and keep moisture in.
Let it Grow
It takes a few weeks to a few months for the new layer to be ready to remove from its mother plant. Roots can grow in as little as four weeks, but most Azalea gardeners start their air layers in spring and leave them to develop until late summer or fall.
While you wait for the roots to grow, check periodically to make sure the wrapping is secure. Birds and critters can sometimes rip open the plastic or foil. If this happens, you may need to wrap it again. Some birds are especially attracted by shiny foil. Remember, the wrapping will keep the roots from drying out and dying.
The layer is ready when roots have grown all through the rooting medium. If you used clear plastic or clamshells (like these), you’ll be able to see them. You can also feel for roots by gently squeezing the bundle or unwrapping it to check.
Cutting and Planting
Once you have a nice root ball, cut the branch off just below the new roots. This is your new Azalea! Take off the plastic or foil, but don’t try to remove the rooting medium, or you could damage the roots.
Plant your new Azalea promptly, either in the ground or in a container. Containers can be a good choice for new layers because you can take extra care of them while they get established, for example, taking them inside to avoid freezing temperatures. Your new plant needs a bit more TLC than its established parent plant.
The Best Time to Air Layer Azaleas
Start your air layers in early spring, usually March or April. At this time, the sap is running, making it easier to remove the bark. Also, you won’t see much root growth at freezing temperatures. If you live in a warm climate, you may be able to start air layers in late summer.
Azalea gardeners usually let air layers develop through the summer and cut them in August, September, or October. If your Azalea grows roots quickly, though, you can cut it and plant it as soon as it’s ready.
The Bottom Line
If you have evergreen Azaleas and want more of them, air layering is the way to go. Just pick a branch, strip a section of bark, tie a bundle of sphagnum moss or coir around it, and wait. Once roots have grown, cut off the branch, and you have a new Azalea ready to be planted! Who knew propagating plants was this easy?