Air layering is a simple and effective way to propagate fig trees and many other species of plants. It involves girdling a branch and wrapping it with a moist rooting medium like peat moss or compost. This added humidity encourages the branch to form roots that can be cut away from the Mother tree to create a new fig tree.
When I first started as a new fig grower, air layering was the first method of propagation I learned, which I guarantee will bring you success when you follow the steps provided in this article. It’s that easy. I'll also disclose my favored methods, the sandwich bag method and air layering even the trunk of a fig tree.
Check out this article to learn more about the many ways of propagating fig trees. Propagating can be an enjoyable hobby due to the multitude of simple methods available, making it easy to create duplicates to share with friends and family.
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When to Air Layer Fig Trees
Air layering is performed during the active growing season. Typically in the early spring or summer. Ideally, you want to aim for an average ambient temperature of around 78F for all fig tree propagation. After accumulating years of experience and conducting a thousand air layers, I concluded that the peak time for root formation when propagating fig trees is around the summer solstice.
If you decide to air layer later in the growing season, keep in mind that the process of air layering from start to finish takes about 2 months on average. That means you wouldn’t want to start an air layer 1 month before your first frost when metabolic rates of fig trees begin to cease.
Here’s What You’ll Need:
A sharp grafting knife
Pre-moistened sphagnum moss, coco coir, potting soil, or compost
A container for the soil. Either plastic pots, one-gallon milk jugs, or quart-sized sandwich bags (depending on your chosen method)
Zip ties, TE Binding Tube, jute twine, or tomato twine
Optional: Rooting hormone
Air Layering Fig Trees: A Step-by-Step Guide
The Sandwich Bag Method
This method makes it easy to perform hundreds of air layers quickly. Credit to Ben B. in Seattle for introducing this method to me.
Select a healthy branch that is at least 1 year in age.
With a grafting knife create a 1-inch wide girdle completely around the branch. Be sure to remove the bark and the cambium layer (the green layer under the bark) revealing the white or yellow hardwood. Do not damage the hardwood.
Prepare the moss or soil: Moisten the moss or soil and squeeze out any excess water. You want the moss or soil to be damp but not soggy.
Fill the quart-sized sandwich bags with pre-moistened soil. Use the Ziploc to seal the bag. Then use your knife to cut the sandwich bag like a hot dog bun. Think of the soil as the bun and the branch you’ve selected as the hot dog.
At the location of the girdle, wrap the branch with the sandwich bag. Make sure the girdle is in good contact with the surrounding soil. Tighten the sandwich bag around the branch with zip ties, TE binding tube, or twine to keep the air layer in place. You do not want the air layer sliding vertically or horizontally along the branch. That could break the new roots that form.
Consider staking your air layer if it’s too heavy and breakage may occur.
After about two months, you should see roots growing through the plastic wrap. Once the roots are several inches long, you can cut the branch below the roots and pot the new fig tree.
Trunk Air Layering
Trunk air layering of a fig tree, initiated 2-3 weeks after your last frost date and removed at the end of the growing season, results in a well-established tree. This method uses a 2-5 gallon-sized pot, and the net result is a larger root system, earlier fruiting, and faster maturity due to prolonged attachment to the mother tree and the potential for regrowth below the air layer to reestablish and train the form.
Select the trunk of a fig tree of your choosing.
Girdle the trunk to expose the cambium, promote callusing, and encourage root development.
Cut a 2-5 gallon-sized pot down its side to the bottom of the pot’s middle drainage hole and wrap it around the trunk.
Fill it in with pre-moistened soil.
Here are some additional tips for air layering fig trees:
Don’t waste your time air layering a dormant fig tree. It must be actively growing and ideally, ambient temperatures are consistently in the 70-80F range.
You can use different types of moss or soil for air layering, but I find sphagnum peat moss or coco coir to be the perfect medium.
Air layering is best performed on 1 year old wood. However, you can air layer growth that’s multiple years in age and while it’s not necessary, I recommend applying rooting hormone to the girdled area to encourage root growth on older wood.
Be patient! It can take 1-3 months for the air layer to finish.
Removing Air Layers: Patience is Key
When removing air layers from your fig tree, patience is key. There is no rush, and waiting until the conditions are ideal will ensure your air layer's success.
Root development is crucial: Wait until the air layer has a good solid root mass filling the container. This ensures it can support the foliage once separated from the mother tree.
Maintain a balance between leaves and roots: This means there should be enough roots present to support the leaves.
Consider removing some leaves: If the root mass is insufficient, remove some leaves to adjust the balance and prevent stress on the newly separated tree.
Wait until frost: Consider removing air layers until after a few frosts have hit your trees. This induces dormancy, eliminating leaves which ensures an easy transition upon removal.
Choose the right conditions: Remove air layers on cloudy, cool, and humid days to minimize stress during the transition.
Removing Air Layers and The Adjustment Period
Once your air layers have developed sufficient roots, it's time to remove them from the mother tree and transition them to their independent life. This process requires careful attention to detail to minimize stress and ensure successful transplantation.
Check root development: Look for hardened, yellowish-brown roots, indicating they're ready for transplantation.
Remove the air layer: Using pruning shears cut away from the Mother fig tree below the air layer.
Remove some leaves: Reduce the leaf surface area to match the root system's capacity. This helps maintain a balanced water uptake and minimizes stress.
Choose a suitable container: Use a larger pot with good drainage to accommodate the air layer's root ball.
Fill the pot with soil: Ensure good contact between the roots and soil by gently shaking the pot and pressing the soil down. However, it is critical not to damage any of the roots.
Place the air layer in the shade: Provide indirect light for the initial few weeks to minimize stress on the newly independent tree.
Monitor the tree: Watch for signs of stress like drooping leaves, and adjust the amount of foliage if necessary.
Gradually introduce more light: Over time, gradually increase the amount of light the tree receives to acclimatize it to its new environment.
Water carefully: Avoid overwatering at the initial stages, as the roots are still adjusting to their new surroundings.