One of the great joys of gardening is propagating new plants by taking stem cuttings and rooting them in potting medium. It's economical because you increase your plant collection for little to no cost (just the soil and pots), and it's fun. There's a great sense of satisfaction involved when you plant a stem cutting that has sprouted healthy roots and watch it develop into a healthy adult plant.
The technique is commonly used to reproduce houseplants, but it also works for many outdoor garden plants. In colder climates, cuttings taken from tender garden plants can be rooted indoors, planted into pots, and grown into healthy mature specimens that can be transferred outdoors the following spring. Although it is a little harder, many woody plants, such as roses and shrubs, can also be reproduced by taking stem cuttings.
There are two ways to root stem cuttings: in water and in a growing medium. Many plants, such as spider plants or pothos vines, readily root in a glass of water and can then be transferred to pots. Others resist rooting in water and require a rooting media—potting soil or a soilless mix—and perhaps rooting hormone and a warming pad to stimulate root growth.
But although people have been rooting plants in water for decades—sometimes with great success—this is usually not the best method to root your plants. The roots that form in water are not the same as roots that form in soil. They tend to be fragile and brittle, adapted to growing in water as opposed to soil or grow mix. When you transfer a water-rooted plant to the soil, many of the roots break off immediately, and the rest shrivel and die as they're replaced by more robust roots adapted to the soil.
When to Propagate by Rooting Stem Cuttings
Stem cuttings can be taken and rooted at almost any time, but the technique is more successful when the plant is not in full bloom. When your goal is to propagate outdoor garden plants over winter, take your cuttings after the plant's bloom period is over, or trim off any flowers or flower buds. A stem cutting that contains flowers or flower buds is putting a good deal of its energy into flower production; it's preferable for the plant to instead put its energy into root development.
- Working Time: 15 minutes to prepare cutting; 5 minutes to plant once cutting is rooted
- Total Time: 2 weeks to 2 months, depending on the type of plant
- Material Cost: About $5 to $10 for a container of rooting hormone
What You'll Need
- Knife or scissors
- Soilless potting mix
- Planting trays and pots
- Rooting hormone
Cut a 3- to 6-inch long cutting from a healthy portion of the stem, using a sharp knife or pruners to sever the stem at a 45-degree angle. This angled cut will maximize the area available for roots to develop. If possible, take the cuttings from newer growth. Herbaceous plants usually root the best, although many woody plants will also successfully root from stem cuttings.
The cutting should have at least two or three sets of leaves along its length. Make sure the cutting includes at least one growth node (a bump on the stem from which leaves or flowers sprout) that can be buried in the growing medium. Roots will sprout from this node, as well as from the cut end of the stem.
Trim the Cuttings
Trim off the bottom leaves from the bottom node on the cutting; usually, you can simply snap off the leaves.
Apply a powdered or gel rooting hormone to the trimmed end of the cutting and to the area where the leaves were removed. With powdered hormone, it helps to first moisten the stem before rolling it in the powder. With gel hormone, simply dip the end of the cutting into the hormone. (Note: Using rooting hormone is optional, but it helps assure rooting of many plants, especially woody plants such as roses and shrubs.)
Plant the Cuttings
Prepare a shallow tray or seedling pot with a soilless potting medium, such as a seed-starter mix or vermiculite. Poke a hole in the medium with a pencil, then insert the end of cutting into the medium. Lightly tamp the mix around the stem of the cutting to provide support and hold it upright.
Tend the Cuttings
Most cuttings prefer to avoid full sun while they root. Instead, try to place the container in a location where it will receive a 50/50 ratio of shade to dappled sunlight. Cuttings thrive on warmth and humidity, and the growing medium should be kept evenly moist but not drenched while roots develop from the cuttings.
Inspect the cuttings every two weeks, looking for new leaf growth and root development. If flower buds or blooms develop, pinch them off while roots are developing. New leaves will assist with root growth, but flowers divert energy away from the roots.
Plant the Cuttings in Pots
When you see new leaf growth developing along the stem of the cutting and healthy roots are established, transfer the cutting to a new pot with fresh potting soil. When you feel resistance when slightly tugging on the cutting, it means the roots are sufficiently developed to transplant the cutting into a pot. A small trowel or large kitchen spoon is a good tool for scooping out the rooted cutting and transferring it to its new home in a larger pot.
When moving rooted cuttings started indoors during the winter back outside, it is important to harden them off to avoid sudden shock. Gradually acclimate them to outdoor conditions with increasingly long daily visits on a deck or patio. At the point where nighttime temperatures are reliably at 50 degrees Fahrenheit or warmer, your specimens can be safely planted in the garden.
Tips for Rooting Stem Cuttings
- You can root many leafy plants from cuttings, but if you find that you're having a hard time with any particular plant, make sure you're not overwatering, that the cuttings have active growth nodes and that the cutting isn't exposed to either direct sun or cold drafts. For particularly difficult plants, try a heated plant mat under the pot to encourage new root growth.
- With shrubs and other woody plants, rooting via stem cuttings is most likely to succeed if you take cuttings from new growth that has not yet become woody. April through June is usually the best time to take cuttings from woody plants. Using a rooting hormone is essential when attempting to root cuttings from woody plants.
- Remove leaves that turn brown or black as the stems are rooting. Discard any cuttings that turn soft or show other signs of rot or fungal disease.