What is marcotting, and why do horticulturists swear by this plant cloning practice?
If You See a Bag of Dirt Tied to a Tree Branch, Here’s What It Means
Published on Jun. 30, 2025
If you’re a gardening geek like me, you might frequently fall down horticulture Reddit thread rabbit holes. One I saw recently was speculating about the seemingly strange phenomenon of small bags of soil tied to tree branches. While this may look random, it’s actually a smart, scientifically proven propagation gardening hack commonly referred to as marcotting.
But what is marcotting, exactly? We asked an expert to dish the dirt on how this reliable air-layering technique works, when you might use it in your garden, and what tips to keep in mind to coax roots out of stems still attached to the parent plant.
What Is Marcotting?
Marcotting—or air-layering—is a valuable asexual propagation method that doesn’t rely on sowing seeds or spores. According to Jeff Wasielewski, Commercial Tropical Fruit Extension Agent at the UF/IFAS Extension, when done properly, it produces a new plant—leaves, trunk, and roots—that is a genetic clone of the parent plant. You do this by wounding and then wrapping a stem or branch while it’s still attached to the parent plant, with the aim of encouraging new roots to form in a moist environment. Once the roots are fully developed, you detach the stem and transplant it.
What Is Marcotting For?
Wasielewski explains that marcotting is helpful if you want to guarantee the new plant will have the same colourful leaves, disease resistance, or flavor of fruit that the parent plant has. However, it’s not just genetic uniformity that makes marcotting a handy propagation technique. By bypassing the seedling stage, you might get to enjoy flowers or fruits sooner. It’s also a reliable, beginner-friendly alternative when you have plants that don’t root easily from cuttings.
Does Marcotting Really Work?
Marcotting is a cost-effective, low-tech propagation technique that has been proven effective and accessible for beginner gardeners. However, Wasielewski explains that air layers don’t produce the strongest roots, and it works best with dicots—with seeds that split in two—like smaller shrubs and woody, deciduous trees.
He explains that it won’t work with things like bananas or palms, as they have a unique trunk structure and don’t generally produce aerial roots. “Air-layering does not work on every dicot, so always research if you can air-layer your plant,” he says.
Wasielewski often uses marcotting with a high success rate to produce new guavas and crotons. Some other examples of easy-to-work-with plants commonly propagated with marcotting include camellias, fruit trees, lilacs, magnolias, philodendrons, rhododendrons, and roses.
How To Marcot
Successful marcotting is all about cutting, wrapping and sealing the right way.
Gather tools
A benefit of marcotting is that you don’t need any high-tech supplies. Just a sterile knife, sphagnum moss, foil sheets, polythene film, ties and twine.
Cut stem/branch
Choose a young, healthy, straight branch. Trim off the side shoots and leaves so it’s snag-free. The layers can vary in size depending on the species, but smaller layers around the size of a pencil are easier to manage.
Make parallel ring incisions around the stem that are about 1 or 2 inches apart. Take care not to cut into the woody part of the stem—the aim is to create a liftable “tongue” that allows you to leave an area of exposed wood on your branch.
“Make clean cuts when you’re removing the phloem [living vascular tissue], and remember to remove the cambium layer [the green layer],” Wasielewski says. Scraping the cambium layer away helps to promote root growth by preventing callus tissue from forming.
Apply rooting hormone (optional)
Applying a rooting hormone can help. However, Wasielewski says he doesn’t use it when working with easy-to-air-layer guavas and crotons.
Wrap the wound
Cover the exposed wound with a generous amount of moist—not wet—sphagnum moss. Hold it in place with aluminum foil.
Seal the wound
Wrap plastic film around the moss to retain moisture. Snugly secure it with twine or tape. If you don’t wrap in aluminum before sealing, use black rather than clear plastic for plants that take a long time to root to reduce the chance of light-loving algae growing.
How To Care for a Marcotted Plant
It can take from a month to a year for sufficient roots to form for transplanting your marcotted plant. During that time, check the air layer every two to four weeks. The sphagnum moss needs to remain moist, and once the roots have covered the sphagnum, cut the air layer off just below the tin foil.
How To Transplant a Marcotted Plant Into Soil
“I like to place the transplant in a bucket of water that has just a pinch of liquid fertilizer in it,” Wasielewski says. “Take the plant to your potting area and put it in a one-gallon container with well-draining potting soil.”
Wasielewski recommends cutting the leaves back by around 30%. “This will cause the plant to lose less water, which is important since it has a new root system,” he says. Don’t try to remove the sphagnum moss as this can damage the roots.
You want to keep the soil moist but not wet, and in a location that receives dappled sunlight. “Once the plant has put out new leaves, check to see if the roots are filling the container,” Wasielewski says. “If so, you can move them to a larger container or plant them in the ground.”
Frequently Asked Questions
When is the best time of year to do air layering?
The best time of year for most air layering is when the humidity and temperatures are up, according to Wasielewski. This is typically from May to September.
Does air layering work in cold climates?
It’s possible to use air-layering propagation techniques in cold climates. It’s most likely to succeed if you opt for the months when the plant is actively growing, and temperatures are at their mildest.
Why is my air-layered plant dying after separation?
Common causes for an air-layered plant dying after separation are insufficient root growth or stress from under or overwatering, too much sun or rough handling.
About the Expert
-
Jeff Wasielewski is the Commercial Tropical Fruit Extension Agent at the UF/IFAS Extension, Miami-Dade County.
Related
