Rosemary is one of the most universal herbs to grow in your garden. It is a drought-tolerant, low maintenance perennial shrub that can be harvested for a variety of uses and it looks great as an ornamental landscape plant. It produces lovely flowers that come in white, pink, purple, or blue and attracts lots of pollinators. The foliage of this plant has a pleasant scent and it’s a staple herb for culinary use. If you would like to add something new to your garden that will stick around for years to come, growing rosemary plants is a no brainer! And luckily, rosemary propagation is extremely easy!
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The name “rosemary” is of Latin origin and means “dew of the sea”. Historically, this herb has been used in rituals and for medicinal purposes by the ancient Egyptians, Romans, and Greeks. Rosemary was thought to strengthen memory and brain function and was symbolic of remembrance.
Today, it is still popular for a variety of uses including décor, fragrance, aromatherapy, and to flavor a variety of dishes. For culinary use, rosemary sprigs are commonly used to flavor soups, casseroles, all types of meat, grains, and potato dishes.
In this article, we’ll teach how to propagate rosemary plants at home using a few easy methods. You can choose the method that best suits the supplies you have on hand or try all the methods to see what you like best!
- Garden Safe TakeRoot Rooting HormoneEspoma Seed Starter Potting Mix
What Is Plant Propagation?
The general definition of propagation is to increase in number. When referring to plants, that means the process of creating new plants through sexual or asexual reproduction. There are numerous ways to propagate plants and some methods work better than others depending on the plant you are working with. Learning to propagate your favorite plants at home is an easy, money-saving way to build up your garden.
Sexual propagation occurs when flowers are cross-pollinated and produce seed. Each seed contains an embryo with the genetic material from two parents. When purchasing seed, you will typically find heirloom or hybridized seed. Heirloom seeds are collected and passed down from many generations, so the characteristics are fairly stable. Hybridized seed derives from a controlled method of pollination in which both parents are known, and thus the characteristics of the cross are known and predictable. However, seeds produced from the resulting plants are genetically unstable and should not be used. New seed will need to be purchased every year when growing hybridized varieties.
Asexual propagation involves using vegetative plant parts such as roots, rhizomes, stems and leaves to create more plants. This method will provide you with genetic clones of your original plants and guarantees the same characteristics. Asexual propagation methods can be done easily with the proper tools and tend to produce full-size plants much faster than planting seeds.
Methods For Propagating Rosemary
Rosemary plants can easily be propagated at home from seed or stem cuttings. Air layering is also an option if you have a large, well-established rosemary plant.
Seeds are inexpensive and can be found at your local garden store. Planting from seed is very easy, but it requires patience as it takes a long time to grow a full-size plant.
Growing rosemary from cuttings is a great option if you already have a rosemary plant and would simply like to have more. You can also purchase plants at your local nursery or garden center and harvest cuttings from them. A cutting is simply a piece of a plant that will be used to propagate another plant. There are a couple of different ways to propagate from cuttings. The quickest method will be rooting the cuttings in potting soil using a rooting hormone. Cuttings from rosemary will root without using the rooting hormone, but it does speed up the rooting process. Rooting powder is inexpensive and can be found at garden stores or online.
Air layering is a quick way to propagate larger plants. This method does require that you have a large, well-established rosemary plant. Air layering involves rooting entire branches by bending them down to the soil and partially burying them to promote root growth. Once the roots have grown, the branch can be cut off of the mother plant and transplanted in a different location.
Below you will find a step by step guide for each propagation method.
Materials You’ll Need For Propagating Rosemary From Seed
- Rosemary seedSeed-starting soil mixClean 2-4 inch pots or plug tray
How To Propagate Rosemary From Seed
Plant rosemary seed no sooner than 10 weeks before the last frost.
Start with a high-quality seed-starting soil mix in a small pot or plug tray.
Plant seeds ¼ inch deep. Keep the soil moist, but not overly wet. The optimal soil temperature for germination is 70-75°F.
Make sure to provide plenty of light from a sunny windowsill or a plant light. If using a plant light, turn on for at least 12 hours per day, but no more than 16 hours per day.
Germination should occur within 2-3 weeks.
Transplant seedlings to a larger pot when the roots are well established in the plug tray or pot. Keep newly transplanted seedlings in a shady location for about a week before moving to direct sunlight.
Materials You’ll Need For Propagating Rosemary From Stem Cuttings
- Mature rosemary plantPruning snipsPotting soil mixClean 4-inch pots or jarMisting spray bottleRooting powder (optional)Plastic bag (optional)
How To Take Cuttings
The first thing you need to learn is how to cut rosemary properly. Ensure your rosemary plant is well watered and has plenty of new growth before harvesting any stem cuttings. Do not take cuttings from flowering stems as they do not root easily and will significantly reduce your success rate.
Select healthy, vigorous stems with new growth and remove the top 4-6 inches using pruning snips. The pruning snips should cut through the stem easily without crushing the plant tissue.
Prepare each cutting by removing the lower leaves exposing 1-2 inches of the stem.
How To Propagate Rosemary Cuttings In Water
Fill a jar or cup with approximately 1-2 inches of water.
Submerge the stems of each cutting in the water. Do not allow the leaves to be submerged in the water. Change the water every few days until rosemary roots develop and keep indoors under indirect light.
Rooting should take approximately 2-4 weeks.
Transplant rooted cuttings into a pot after a small root ball has formed. Keep the transplants in a shady area until roots establish in the pot.
How to Propagate Rosemary Cuttings In Potting Soil
Start by filling a 4-inch pot with a high-quality potting mix. Water the potting mix until completely saturated.
Dip the stems of each cutting into a rooting powder (optional). Stick 3-4 cuttings evenly spaced, about 1 inch deep per 4-inch pot.
Keep the soil moist and keep the pots in a shady location to prevent the cuttings from drying out. If the cuttings start to look stressed, mist with a spray bottle every 1-2 days. A clear plastic bag may also be used to cover the pots to retain moisture and humidity.
Transplant the new plants to a bigger pot or in the ground after roots are well established.
Learn more: Caring For Your Plant Cuttings
Materials You’ll Need For Propagating Rosemary By Air-Layering
- Mature rosemary plantSharp knifeStake or weight
How To Propagate Rosemary By Air-Layering
Spring is the best time of year to air-layer rosemary.
Select a long healthy branch from a well-established rosemary plant.
Bend the branch down to the soil. Dig a hole deep enough to bury the stem where the branch touches the soil.
Remove the leaves from the section of the stem that will be buried. Using a sharp knife, peel and scrape the outer layer of the stem. Be sure not to cut through the stem. This wound is where the roots will start to grow.
Bury the cut portion of the stem in the soil leaving the top portion of the branch above the soil. Use a stake or weight to hold the branch down in place.
Keep the soil moist. Check every few weeks for root development. After a root ball has formed, separate the plants by cutting the branch connecting the mother plant to the new plant. Transplant the new plant into a container or in the ground in a different location.
Learn more: Air Layering
Frequently Asked Questions
Q: Can you propagate store-bought rosemary?
A: Yes! If the rosemary is freshly cut, you should be able to use them for cuttings. If the stems are not fresh, they may be dehydrated and your success rate will be low.
Q: How long does it take for rosemary to grow from a seed?
A: It takes about 3 months to grow rosemary plants from seed. Germination takes 2-3 weeks, then the plants require a few months to increase in size.
Q: How long does it take for rosemary cuttings to root?
A: Rooting rosemary will take between 2-4 weeks to root depending on the method used. Sticking cuttings in potting soil using a rooting hormone will result in faster rooting times.