Propagating Plants by Layering

Vegetative plant propagation is a way for one plant to create another plant without the need for pollination to occur. This process is often much faster in achieving a new plant than growing from seed.  The genetics of the parent plant can be carried on through this vegetative propagation method.  There are many methods to propagate plants and the one covered in this article was taught to me by my grandmother many years ago – layering.  Layering is a science and an art and has been performed by humans for over four thousand years. 

Propagating plants by layering can be accomplished in several ways, including simple, tip, air, mound, compound, and runner production layering methods.  Many plants in nature propagate by layering accidentally when long, low-lying limbs contact the soil around the plant and are eventually covered by leaves from other surrounding trees and shrubs.  This creates an organic cover over a part of the limb and keeps the area moist.  This creates the situation for adventitious roots to develop at the soil contact area.  This occurrence is called simple layering and is often mimicked by gardeners in the landscape.  Not all plants respond to this type of propagation, but several common species that do are azaleas, jasmine, viburnum, climbing rose, and grapevines. 

Unlike simple layering, tip layering involves digging out a shallow 3–4″ hole, which will allow space to bend the end of the branch down into the hole with the tip out the other side.  Then, simply cover the hole to keep the branch in the ground.  It may take something with a little weight placed over the covered hole to keep the branch from popping out.  A brick or rock may be all that is needed.  Both methods will take months for enough roots to develop before clipping the branch with a new plant ready to be dug and set somewhere new.  For best results with both simple and tip layering, begin either in early spring with last seasons growth or late summer, utilizing that current year’s growth. 

Air layering is a fun adventure to rooting a new plant and can be used with both outdoor and indoor plants.  It can be used on outdoor plants like camellia, azalea, maples, and magnolia, or indoor plants including weeping fig, rubber tree, and dieffenbachia.  This type of layering requires a bit more planning and preparation than simple or tip layering.  If the plant has a bark layer surrounding the cambium layer (this is the growing part of the limb and trunk and appears green) this area will need to be removed with a sharp clean knife.  Choose a 1- ½ inch long area of the limb and scrape this area to remove the cambium layer located just beneath the bark. This is done to prevent the outside limb area from reconnecting back to the limb portion connected to the plant.  Sphagnum moss will be needed to wrap around the wound site to create a rooting zone.  Be sure to soak the moss with water by immersing it in a bucket of water, then squeeze it out.  Wrap the moss with plastic wrap, making sure the moss is fully covered and tucked inside of the plastic.  Both ends of the plastic wrap need to be secured tightly with twist ties or string.  Make sure it remains tight throughout the 2 – 4 months needed for rooting to occur.  If this process takes place in a sunny location, cover the plastic wrap with tin foil to block out the light. 

There are other methods to layering plants and if you are interested, search online through the University of Florida IFAS EDIS site or contact your local UF IFAS Extension office in your local county.  Enjoy growing your new plants.