Plant Propagation

Plants reproduce in different ways: seeds, spores, rhizomes, bulbs, and tubers. But you can make new plants, too.

There are many different ways to make new plants, and the best method will vary depending on the plant you are propagating. Plant division, air layering, and cuttings are different ways that you can turn one plant into many.

Dividing

In Florida, early fall is a good time to divide bulbs. Plants that develop these underground reproductive units, such as amaryllis, develop “baby” bulbs which, when grown to full size, are known as offsets. To divide bulbs, simply separate these offsets and replant them to create new plants.

Perennials are also great plants for propagation by division. Perhaps you’ve noticed some of your perennials looking a bit raggedy, producing smaller flowers (if they’re flowering at all), or even a hole appearing in the middle of a clump. If so, it’s probably time to divide the plants. Dig them up and break the plants into smaller clumps, being sure that each section has a good number of roots and leaves. Be sure these “new” plants get in the ground quickly. The best time to divide plants is after the blooming season or during milder times of the year. Dividing perennials increases their vigor and conversely, keeps rapidly spreading plants from taking over.

Air Layering

Air layering involves starting a new plant while it is still attached to the parent plant. This method is often used to propagate woody shrubs and trees. You can attempt air layering by choosing a short section on the parent plant that you would like to root. Create a wound in the bark between the young plantlet and the rest of the plant and apply rooting hormone to the cut. Cover the wound with sphagnum moss and plastic wrap until roots form. Once your plantlet has successfully formed roots, you can separate it from the parent plant, and relocate it to another place in your garden.

Cuttings

Cuttings are a popular method of plant propagation, with many people using stem or root cuttings. But some plants, like sansevieria (snake plant), can be propagated from a small piece of a leaf, and others like African violet, hoya, and peperomia can be propagated from a leaf and petiole (the stalk supporting the leaf). With large-leaved begonias, cut several major leaf veins and lay the leaves flat on the soil. New plants will form where you made the cuts.

With root cuttings, you’ll want to be sure to keep the cuttings in a cool, semi-shaded area to avoid “cooking” them. A key factor in successful propagation from root cuttings is maintaining a moist and humid environment. A mist bed is one way to ensure cuttings don’t dry out. This device features a nozzle that periodically puts out a small burst of mist.

You can find instructions online for building your own, but a mist bed can be complicated (and expensive) to set up and maintain and is usually not necessary for home propagation. An alternative approach is to stick the cuttings in pots of moist sand or potting soil and cover them with a clear plastic bag, a clear plastic bin with a lid, or even an inverted two-liter bottle with the top cut off. This creates a “greenhouse” effect, keeping the air humid around the cuttings.

When working with stem or leaf cuttings, they should be placed in bright, indirect light and the potting media should be kept moist until new plants develop.

Rooting Hormones

When propagating plants by air layering or cutting you may want to use rooting hormones to speed up the process and ensure greater success.

Rooting hormones occur naturally in plants but are also commonly available at garden centers in powdered form. These powders provide supplemental amounts of auxin, a natural plant hormone that helps with root development. They may also include a fungicide.

When using rooting hormones, pour a small amount of the powder into a small dish so that you don’t contaminate the remaining product.

For more information on propagating plants and which method is best for a specific plant, contact your county Extension office.