Propagating rosemary plants has become one of my favorite tasks in my herb garden. It is a fun and simple process, and when performed correctly, propagating your own rosemary can save you money and provide plenty of plants to share with neighbors and friends. In this article, I’ll fill you in on how I propagate rosemary using two different methods.

Why propagate your own rosemary

A woody perennial herb, rosemary—like lavender and thyme—is super easy to propagate at home, even if you aren’t a very experienced gardener. Soft-stemmed herbs, like basil and tarragon, are equally as easy. The propagation process is very straightforward and requires just a few tools and materials.

Before we get to the how-to steps, you may wonder why you should bother taking rosemary cuttings when the plants are so readily purchased at your local nursery. The biggest reasons why I regularly grow rosemary from cuttings are:

• I can grow dozens of plants from a single mother plant, saving me from purchasing new plants each season
• It’s easy to overwinter rosemary as small stem cuttings, instead of trying to overwinter a giant pot of rosemary (which I never seem to be successful at despite my degree in horticulture)
• I love having the rooting stems in the kitchen where I can snip off a few leaves for cooking every now and then all winter long
• It is always enjoyable to watch a cutting take root—plus, it’s great for your gardening self-confidence!

Now that you know why you should be propagating rosemary at home, here’s when and how to do it.

The best time for propagating rosemary

Rosemary (Salvia rosmarinus; syn. Rosemarinus officinalis) is a frost-sensitive herb native to the Mediterranean region. It requires full sun and good drainage. This means the plants do not typically survive the winters here in my Pennsylvania, USDA Hardiness Zone 5 garden, not only because of the cold winter temperatures, but also because of our poorly drained clay soil in winter.

If you live in a milder climate than I do, rosemary may be a perennial. If it is a perennial where you live, the plants can be propagated at any time. Most growers, however, choose to take cuttings in early spring (after the flush of new growth) or in the late summer.

Since it is sensitive to frost and I live in a cold climate, I focus most of my rosemary propagation efforts on the end of the growing season, just before the arrival of the first frost. This is because I want to overwinter the cuttings and replant them into the garden the following spring.

However, this is not the only time for propagating rosemary where winters are cold. Really, cuttings can be taken at almost any time. Cuttings taken in the spring will root quickly and go on to grow and produce flavorful leaves all summer long. Cuttings taken in the summer will be well-rooted by fall and can be grown all winter in the protection of a greenhouse, hoop tunnel, or your home. Cuttings taken in the autumn (like mine) will root as they overwinter, giving you lots of vigorous plants just in time for spring.

How to take a cutting of rosemary

Now that you know why and when to propagate rosemary, let’s talk about how to take your cuttings.

First, select a mother plant that’s free of pests and diseases. This is important; you don’t want your new little ones to be sick from the start. Next, since these are woody stems, you’ll need a sharp scissors, small pruning shears, or a knife. Make sure it is clean. I like to disinfect the blades with a spray of Lysol or pruning disinfectant prior to taking my cuttings.

The practice of taking stem cuttings is very much like pruning. You’ll want to cut off a portion of the stem that includes at least three clusters of leaves, cutting it just above a leaf node. I like to cut it at a 45 degree angle, but this isn’t necessary. A blunt cut works just fine. Cuttings can consist of green stems in the spring or summer (known as softwood cuttings), or they can be woody stems in the autumn or winter (known as hardwood cuttings).

Each cutting should be about two to four inches long. You can take terminal cuttings (the tip of the stem) or medial cuttings (further down on the stem; does not include the tip). Sometimes I cut a long branch off and then cut it down into one terminal cutting and three or four medial cuttings. On medial cuttings, two new branches will develop from the topmost leaf nodes.

Immediately proceed to the next step. Try not to keep your severed cuttings longer than a few minutes before placing them in their rooting medium. Otherwise, you risk them drying out and the cuts callusing over.

Two ways of propagating rosemary cuttings

There are two different ways to root your new rosemary cuttings. One involves rooting them in water and the other roots them in a solid growing medium like potting soil, sand, or vermiculite. Let’s talk about each of these two methods in turn.

Propagating rosemary in water

The first (and easiest) method of propagating rosemary is in water. It works especially well for hardwood cuttings in the fall. Softwood cuttings tend to rot in the water before they can root. For this technique, you’ll need a few small jars or containers of water. Clean them thoroughly prior to use and fill them with tap or filtered water (no need to use distilled).

Strip all of the lower leaves off of each rosemary stem so that no leaves will be located beneath the water level. If any leaves are in the water, they’ll encourage bacteria growth that can clog the stem. I like to save these stripped leaves for a batch of roasted potatoes so they don’t go to waste!

Next, insert the base of the cutting into the jar of water, making sure a few inches of stem are submerged. Take plenty of cuttings because not all of them will root. In as little as a week, you’ll start seeing new roots forming from the base of the stem. Before you know it, the roots will be filling the container.

Change the water and rinse out the container every 10-14 days, or whenever it starts to get cloudy. Give the roots a quick rinse and then stick them back in the water. You can keep your rooted cuttings in water for a few months, but eventually you’ll want to pot the rooted cuttings up (more on how to do this in a later section).

Propagating rosemary in soil

The second method of propagating rosemary is in a solid growing medium. This can be sterile potting mix that consists of peat moss or coir fiber and perlite; sand; or vermiculite. If you choose to use potting mix, be sure it is a brand new bag and that the packaging notes it is sterile. Otherwise, you run a higher risk of developing rot.

The materials you’ll need—aside from the growing medium—are a few clean, small pots with drainage holes, plastic baggies or a clear humidity dome, and rooting hormone powder.

Take each cutting and strip off the lower leaves. Dip one to two inches at the base of the stem into the rooting hormone powder, tapping off the excess. Then insert the stem firmly into the pot filled with growing medium. Make sure one or two bare leaf nodes are below the soil surface. You can insert several cuttings into each pot. Water the cuttings in well.

Put the cuttings, pot and all, into a clear plastic baggie fastened shut with a twist-tie. Or, put a clear humidity dome over the pot. Leave the cover in place for three to four weeks, until the cuttings have taken root. Water the medium as necessary, ensuring it always has ample moisture but is not sopping wet. Once the cover comes off and your cuttings have rooted, you can reduce watering to once a week.

Caring for the cuttings

Regardless of which method of propagating rosemary you chose, it’s essential that you care for the “baby” plants carefully. Place them on a bright windowsill with indirect light; never in direct sunlight.

There is no need to cover cuttings rooting in water because they have consistent access to water and, as it evaporates from the container, it raises the humidity around the cuttings.

The biggest danger to your new plants is root rot, which does happen from time to time, especially if you don’t use sterile potting mix.

With the right care and attention, before you know it, you’ll see signs of new growth on both the stems and the roots. New shoots are always exciting to see! Once that happens, it’s time to pot up your new rosemary plants.

How and when to pot up rosemary cuttings

When propagating rosemary, eventually the rooted plants may outgrow their containers or become crowded before you’re ready to move them outside into the garden. If this happens, it’s time to pot them up into a new, slightly larger pot with fresh potting soil. If the cuttings are amply rooted, you can add a bit of compost to the potting soil to help feed the new plants. Until they have roots, however, do not fertilize the cuttings.

When the danger of frost has passed, the plants can be moved out into the garden.

Reap the rosemary rewards

Come late spring or early summer, your rosemary propagation efforts will really pay off! You’ll be able to fill your garden and containers with new home-propagated plants, saving yourself a trip to the garden center for this tasty herb. Make it an annual fall tradition and you’ll always have rosemary indoors for the winter. There’s no harm in pinching off a sprig or two for cooking either. I hope you’ll find propagating rosemary as easy and fun as I do.

For more on growing rosemary and other herbs, please check out the following articles:

• Growing rosemary in gardens and pots
• Harvesting rosemary for fresh or dry use
• How to grow your own catnip
• Tips for trimming basil
• A beginner’s guide to herb gardening