GARDEN CAPSULE
The challenge: You have some houseplants that are getting too tall and leggy, with long, bare, ugly sections of stem.
The solution: Use air layering to renew plants such as rubber plant, croton, dieffenbachia, Norfolk Island pine, diffenbachia, corn plant, schefflera or weeping fig.
Start by soaking several handfuls of sphagnum moss in warm water. Then make a slanting cut about a fourth of the way through a leggy stem. Using a toothpick to hold the cut open, stuff some rooting hormone powder into the wound. Then lightly squeeze excess moisture out of the moss and pack it around the wounded area. Cover the moss with a sheet of clear plastic, held in place top and bottom with twist ties. Check periodically and add a little more water at the top if the moss dries out.
When new roots have grown throughout the moss, sever the newly rooted stem from the mother plant. Loosen the moss just a little from the roots and then pot the “new” plant in fresh potting soil.
Pluses: While many houseplants have stems that root readily from cuttings, air layering is the only practical method for renewing or propagating plants that have large leaves or thick or woody stems.
Minuses: Air-layering is not a quick fix; you may have to wait several months before new roots form. Keep watch through the clear plastic wrap until you see that new roots have grown throughout the ball of sphagnum moss.
Sources: Rooting hormones are readily available at garden centers. Most houseplant books have a section on propagation, including air-layering. For stepby-step instructions with illustrations, see “How to Air Layer a Houseplant” at https://store.exten sion.iastate.edu/ (search “PM268”).