What Is Air-Layering?

In my parents’ wooded backyard in Charleston, South Carolina, thick beds of glossy camellias thrive in the dappled sunlight and deep shade. But few, if any, of the evergreen shrubs with their elegant winter blooms came from the local garden center. Instead, they’re the result of a lifetime of work. The prized collection of around thirty plants was transplanted from my grandmother’s garden as well as that of my great uncle, other family members gifted with green thumbs, and even the grounds of an old bank building in downtown Charleston. These heirloom plants were propagated one at a time using a traditional gardening technique called air-layering, and although it takes longer to form a new plant via air-layering (as opposed to propagating from cuttings), the method is relatively approachable. With a little direction, it’s easy for the average home gardener to execute. 

What Exactly Is Air-Layering?

“Air laying is just one type of propagation technique,” says Carmen Ketron of Clemson University Cooperative Extension. And while propagation sounds intimidating, the whole process is easier than the terminology implies. “All you’re doing is taking a piece of the plant and wounding it—you’re not removing it. The great part about these plants is that if you wound them in the correct way adventitious buds will actually turn into roots, and where you would normally see a leaf growing on a branch, wounding it and providing it with moisture and a continuous flow of nutrients will turn those buds into a new root system instead.” 

A few months after creating the initial wound, you should be able to cut and replant a perfectly cloned plant, which features the exact characteristics (color, size, etc.) of the mother plant. 

What Are The Benefits Of Air-Layering?

Propagation via cuttings yields a similar result, but Ketron likes air-layering for its simplicity and affordability. The new root system grows on the parent plant with little intervention on behalf of the gardener. “There’s less fussing around with air-layering,” she says. “You don’t need a greenhouse or a whole bunch of fancy supplies. It also takes up less space because the new growth happens on the existing plant.” 

Additional benefits to air-layering include: 

• The ability to save and reproduce rare or discontinued varieties: “Air layering is perfect for plants that you can’t find anymore. I air-layered a few of my grandmother’s roses. She was a rosarian and had some really hard to find varieties.”
• A more mature plant that’s already two feet or taller at the time of replanting.

What Time Of Year Is Best For Air-Layering?

Spring is generally considered the best time of year to air-layer camellias—March, April, or May—because the plants are actively growing.   

What Equipment And Materials Does Air-Layering Require?

Other than plenty of patience—it takes several months for new roots to form—you’ll need a few basic supplies: 

• A mature camellia plant.
  
• A sharp knife: “I have cut myself many times trying to do propagation like this,” Ketron says. “And a dull knife makes injuries much more likely.” 
  
• Sphagnum moss: “Not to be confused with Spanish moss,” she says. “This wet moss makes a nice webbing and gives us the continuous moisture we need for the new root system to grow.” Most local garden centers will carry sphagnum moss. Note: You’ll need approximately two handfuls per new plant you wish to create.
  
• Clear kitchen plastic wrap. 
• Heavy duty aluminum foil.
• Twist ties or electrical tape: “You want something that will hold up in the elements,” she says.
• Rooting hormone (optional): “Some people like to put a rooting hormone down. This helps stimulate those adventitious cells, but if you’re doing it right, you don’t truly need it,” Ketron says. 

How Do You Air-Layer Plants?

• Soak your sphagnum moss in water for at least two hours. (Note: Moss that has been soaked overnight is even better but not a dealbreaker.) 
• Choose a healthy branch about the thickness of a pencil. “If the branch is diseased or dying, the disease will transfer to the new plant,” Ketron says. A sick limb may also cause your attempt at air-layering to fail altogether. Tip: Look for branches without discoloration or deadwood. And when the bark is peeled back, the branch should be “nice and green on the inside.”
• Remove a ring of bark, approximately two inches in length. Starting one-to-two-feet back from the tip of the branch—just below a node, where the leaf attaches to the stem—make two shallow, parallel cuts two inches apart. Finally, connect those cuts, and the bark should peel off in one or two pieces, revealing the cambium layer. 
• Using your knife, gently scrape away the green cambium layer. 
• If you choose to use one, add the rooting hormone. Dust the rooting hormone over the wound/exposed branch you just created by scraping away the cambium layer.
• Wring out your presoaked sphagnum moss.  
• Wrap two handfuls of the sphagnum moss around the wound/exposed branch.
• Snuggly cover the moss in plastic wrap. “Secure the plastic wrap with twist ties or electrical tape to maintain that warm, moist environment,” Ketron says. “The result will almost look like a little candy, like a little peppermint candy wrapper. It should be snug against the branch. We don’t want to leave room for air to dry it out.” 
• Wrap the ball of plastic-covered moss in heavy duty aluminum foil. “The tinfoil is important to reduce sunlight,” Ketron says. 
• And now you wait. If you began the air-layering process in the spring, a new root ball should have formed by fall. You can check the progress of your plant as often as once a week or as little as once over the summer by carefully peeling back the tinfoil. “If the moss looks dry, you can use a squirt bottle to rehydrate and then rewrap with a nice tight seal,” Ketron says. 

How Do I Care For My New Plant?

“Once you see the roots it’s time to cut and replant,” Ketron says. “Carefully remove the tinfoil and cut the plastic wrap before gently pulling away the moss so you don’t snap the roots.” Cut just below the root ball, where you made the original wound, and immediately put the new in water or a soil medium. “We like a soilless potting mix, which you can find it at your local garden center. You can plant the new specimen in a pot, which makes it easier to maintain moisture while the roots get settled, or you can put it right into the dirt with good irrigation.” 

Besides Camellias, What Other Plants Are Suitable For Air-Layering?

“Air-layering works on a number of woody plants,” Ketron says. “Camellias, of course, but also magnolias, azaleas, roses, and Japanese maples, among others.”