The best method to rejuvenate your rubber tree is to propagate it by air layering. This process will take a month or longer to generate a new, shorter plant.
To air layer:
• Remove leaves and twigs on the selected limb 3 to 4 inches above and below the point where the air layer is to be made (usually 8 to 15 inches below the tip of the branch).
• Wound the branch just beneath a node to induce rooting.
• One method: Remove a 1/2- to 1-inch ring of bark and, with a knife, scrape clean the wood underneath. Doing so ensures complete removal of the cambium layer, a layer of cells between the bark and wood. If this layer is not removed completely, new bark may develop instead of roots.
• A better method: Make a long slanting cut upward about one-quarter to half-way through the twig. Keep the incision open by inserting a bit of sphagnum moss or a toothpick to prevent the cut from healing over. A thin bamboo stake or stick tied to the stem above and below the wound will keep the stem from breaking at the wound.
• Apply a rooting hormone around the wound on hard-to-root plants to hasten rooting; hormones are unnecessary for most air layering.
• Bind the wounded area with a handful of moist sphagnum moss. Squeeze excess moisture from the moss before placing it completely around the stem at the wound. Tie the moss firmly in place with twine.
• Cover the moss with plastic film (recycled bread bags work best), and then wrap with heavy-duty aluminum foil, crimped tightly to the stem above and below the ball to reduce water loss and block light.
• Check every 7 to 10 days for moisture.
When roots have developed in the sphagnum ball (one month to a year later), cut through the stem below the new roots and pot up the rooted branch. You can discard the original plant or use it for additional air layering.
