How to Grow New Plants Through Propagation
Authored by Jodi Torpey
Plant propagation may seem like a technical topic for professional horticulturists, but don’t let the terminology intimidate you: If you garden, you’ve likely already propagated plants yourself. If you’ve ever planted a seed that’s grown into a plant, you’ve succeeded at one method of propagation.
Along with planting from seeds, other common methods of plant propagation, which simply means reproducing plants, include dividing existing plants and using plant cuttings to create more plants.
Propagating is a budget-friendly way to double or even triple the number of plants in your garden. You can have more plants for sharing, keep short-lived perennials growing, and keep plants from overcrowding.
3 easy methods for propagating plants
Nature propagates plants by sending up new plant shoots, usually in spring. You can follow nature’s lead to propagate plants yourself. The most common methods are easy: dividing perennials, taking cuttings, and layering plants in the ground.
Here’s how to get started with each.
Method 1: Propagating plants by division
Dividing perennials is one of the simplest methods for getting new plants because it takes advantage of a plant’s natural tendency to spread. Mature perennials that grow in clumps sometimes need to be thinned to keep them healthy and blooming.
When perennials begin to produce fewer flowers or show a dead spot in the center, it’s time to divide them. Wait to divide plants before or after they bloom. For plants that bloom in spring to and summer, wait until late summer or early fall.
Types of plants best suited for dividing
Good candidates to propagate by division include ornamental plants like aster, bee balm, black-eyed Susan, coreopsis, coral bells, daylilies, ferns, hostas, irises, lily-of-the-valley, ornamental grasses, penstemons, peonies, phlox, salvia, and yarrow.
Materials needed to divide perennial plants:
- A sharp shovel or garden fork
- Containers (optional)
- Potting soil (optional)
How to divide perennial plants:
Plan to work on a cool or cloudy week to reduce transplant shock.
1. The day before dividing, water plants to make digging them easier.
2. Prepare the new planting site or get containers ready for repotting.
3. Use your shovel or garden fork to carefully dig around or through the plant clumps to get as many roots as possible.
4. Replant and keep plants watered until they start to grow. For repotted plants, keep them in the shade until they look healthy and strong enough to transplant.
Method 2: Propagating plants with cuttings
Sometimes plants won’t need dividing, are difficult to divide, or can’t be dug up because of their location. To propagate these plants, gardeners use cuttings they grow in soil, sand, water or another medium. Cuttings can be taken from a piece of stem, part of the root, or a single leaf. The cuttings will grow to be identical to the parent plant.
Cuttings can be clipped at any time while plants are healthy and growing, but before and after blooming are especially good times for clippings since plants can focus their energy on growing roots and leaves instead of flowers. When propagating plants with cuttings, it pays to take your time and be patient.
Stem cuttings - Stem cuttings use small pieces of a stem with leaves or buds attached. You can cut stems from actively growing garden flowers and houseplants. When taking stem cuttings, cut and process only a few stems at a time. Use several small containers instead of one large container to prevent something unfortunate from happening to the whole batch of cuttings.
Types of plants best suited for stem cuttings:
Plants that root easily as stem cuttings include aster, bee balm, catmint, chrysanthemum, clematis, delphinium, geranium, Russian sage, salvia, sedum, and houseplants like golden pothos.
Materials need to propagate plants by stem cuttings:
- A pruner or scissors
- Clean and sanitized pots or containers
- A sterile growing medium (like a balanced mix of perlite and vermiculite)
- Rooting hormone
- Plastic bags
How to propagate by stem cutting:
1. Cut off a 6-inch piece of stem below a leaf joint and remove lower leaves.
2. Dip the cut end of the stems into a small amount of rooting hormone and set the stems into the soil in your pots or containers.
3. Water and cover the pots with plastic.
4. Check for soil moisture daily and water to keep stems moist. Roots should form in three to four weeks and will be ready for transplanting.
Propagate plants by root cuttings:
Root cuttings - A few plants can be propagated by root cuttings that are taken when the plants are dormant, which means you should wait until the plant has stopped growing to collect root cuttings. Each root can grow a few new stems, with each stem producing its own roots.
Types of plants best suited for root cuttings:
Horseradish, oriental poppy, phlox, and tuberous begonias.
Materials needed for propagating plants by root cuttings:
- A hand trowel or shovel
- Clean and sterilized containers
- Sterile growing medium (like a balanced mix of perlite and vermiculite)
- Plastic bags
How to propagate by root cuttings:
1. Using your trowel or shovel, dig up the plant and cut off 2 to 3 inches of root. Replant the rest of the root.
2. Place the cuttings horizontally on the rooting medium in your containers and cover with damp soil.
3. Put the container into a plastic bag, place it where it can get bright light and keep the soil moist. It will take several weeks for new shoots to start growing.
Propagate plants using leaf cuttings:
Some plants can be propagated using one leaf because each leaf has a small stem that can grow roots. Leaf cuttings can be taken at any time from healthy plants.
Types of plants best suited for leaf cuttings:
African violets, begonias, bush-type peperomias, and Sansevierias (commonly known as snake plants).
Materials needed to propagate plants with using leaf cuttings:
- Sharp sterilized scissors or a pruner
- Rooting hormone
- Container
- Planting medium (like a sterile potting mix)
- Plastic bag
How to propagate by leaf cuttings:
1. Using your scissors or pruner, cut a leaf from the plant along with 1 or 2 inches of leaf stem (petiole) that connects the wide part of the leaf to the plant.
2. Dip the stem in a rooting hormone to stimulate root growth and place it in moist soil in your container. Put the container in a plastic bag.
3. Give the planted stem bright light and wait for new plantlets to form, then replant each small plant in an individual container.
Method 3: Propagating plants by layering
Ground layering is a way to give old plants new life by encouraging roots to grow along stems that are still connected to the parent plant. When roots start to grow, the stems are cut from the original plant to become a completely new plant. Ornamental shrubs and vines often layer on their own, but you can easily help them along.
Ground layering works best in spring when plants are growing and stems are still flexible.
Types of plants best suited for layering:
Good candidates for layering include plants with creeping stems or upright, flexible stems that bend without breaking. These include blackberries, campanula, climbing roses, currants, dianthus, forsythia, junipers, raspberries, rhododendrons, and spirea.
Materials needed to propagate by layering:
- Shovel or hand trowel
- Landscaping pins, wire, hairpins, or a rock to hold stems in place
How to propagate plants using layering:
1. Select a plant for ground layering and trim off all but a few of the top leaves.
2. Loosen the garden soil, gently bend the stem to the ground, and bury it about 2 inches deep in the ground.
3. Keep the leafy stem tip above the soil and hold the rest of the stem in place with landscaping pins, bent wires, hairpins, or a rock.
4. Water the soil and keep it moist.
5. Roots will form after a few weeks. Cut the new plant from the mother plant and transplant right away or wait until the next season to cut and replant in a new location.
Be patient with plant propagation
Give your new little plants plenty of TLC while they’re growing roots. And be prepared for a failure or two because not every plant or method will take right away. If at first you don’t succeed, try again. It may take a few attempts to get the results you want.