All About Growing Rosemary From Seed

Your kitchen garden will not be perfect if you do not have rosemary in it. This herb is very useful. You can use it to flavor various recipes. In addition, the rosemary plants can make your garden more attractive. Growing them along a path in your garden is a great way to have an aromatic garden. If you want to have this plant in your garden, you can start growing rosemary from seed.

History of Rosemary


This herb is indigenous to Mediterranean areas. It is believed that Egyptians had used rosemary since 5000 BC. They used this herb in burial rituals. The Greeks and Romans used rosemary for medical purposes. In addition, they also used it to repel evil spirit.

From Mediterranean, merchant and explorers spread rosemary to other countries. Therefore, people in China knew about this herb. Rosemary was naturalized in this country in the 220 AD. Meanwhile, the Romans brought rosemary to England, but the exact time is unknown. It was in the 8th century that Englishmen grew rosemary in the farms and monastic gardens.

Later on, this herb was introduced to America in the 17th century. These days, rosemary has been naturalized in various countries. People use the leaves mainly for cooking. In addition, this herb is extracted into rosemary essential oil. This essential oil is good to keep insects away. Some people also use it to promote hair growth.

Rosemary Plant Description


Many people often buy rosemary leaves from the grocery stores. However, not all of them know what rosemary plant look like. If you want to try growing rosemary from seed, you must find out more about its appearance and characteristics.

1. Shape and size

Salvia rosmarinus or rosemary is a warm season crop. This herb gets its new official name in 2017. Before that year, the official name of this plant is Rosmarinus officinalis. Rosemary is an evergreen shrub. This bush has woody branches. It will grow up to 2 m tall in the right environment.

In the first few years, the growth of this herb is slow. But, when it is quite mature, they can be quite tall. In addition, a rosemary bush usually has a long lifespan. You can expect it to grow in your garden from 15 to 20 years.

2. Leaves

This perennial herb shrub has needle-like leaves. They are stiff and about 2 cm long. Moreover, the surface of the leaves is green and shiny. Meanwhile, their underside is gray. Those leaves have powerful flavor and piney aroma. In addition, these flavor and aroma remain the same even when the leaves are dried.

3. Flowers

A rosemary bush will bloom in the second year and every year after that. In a temperate climate, it blooms in the spring and early summer. But, in warmer regions, it is flowering constantly. Rosemary flowers are blue. However, certain cultivars have pink or purple flowers.

Those flowers attract certain species of bees to come to them. Later on, the flowers will develop rosemary seeds. Therefore, you can get the seeds from the dried rosemary flowers.

4. Propagation

This herb can be propagated in two methods. One of them is propagated from cuttings. Some gardeners think that it is easier to grow this herb from cuttings. However, you may find a little difficulty in getting the cuttings, unless you already have this plant or your friends grow rosemary.

The second method is growing rosemary from seed. It can be a bit challenging since the seed has low germination rate. The seed needs about 3 to 4 weeks for the seeds to germinate. If you are growing rosemary from seed, you can purchase the seed online or at your local nurseries.

Basic Requirements Growing Rosemary from Seed


Since rosemary comes from a warm region, it will grow best only in certain condition. In consequence, before growing rosemary from seed, you had better check these requirements.

1. Hardiness zones

This herb is hardy. It can adapt to various hardiness zones. They grow well in USDA hardiness zones 6 through 9. Therefore, if you live in those zones, you can consider growing rosemary from seed at home.

However, the best region to grow this shrub is the region in zone 9. Some cultivars can be planted in zone 8 and cooler. But, you must overwinter the plant or grow it in a pot.

2. Temperature

This perennial shrub grows optimally in the temperature of 6oC to 24oC. Rosemary can survive mild winter if the average temperature is warmer than -3oC. It may tolerate temperature of -3oC, but only occasionally.

3. Soil

The quality of the soil plays important role in your success of growing rosemary from seed. The soil must have well drainage and moderate level of organic matter. In addition, the pH level of the soil is between 6 and 7. Most importantly, rosemary grows well in loamy soil.

4. Water

A rosemary bush doesn’t need lots of moisture during their growing season. It is okay to allow the soil around the plant to dry between watering. However, when you are growing rosemary from seed, you need to keep the soil moist during the germination process.

For best result, you must water the plant once a week or once in two weeks. It is important to avoid over watering the plant. When the soil is too wet, rosemary will suffer from root rot and other plant diseases.

5. Sun

To have thriving rosemary, you must grow this shrub in full sun. Therefore, you need to choose a planting spot that gets at least 6 hours of direct sun a day.

Steps of Growing Rosemary from Seed


Some online stores offer you with rosemary seed packages. Therefore, you can start growing rosemary from seed anytime the weather is suitable for it. The seed is slow to germinate. But, if you are patient and know what to do in growing it, you can be successful in it.

1. Germination

In order to increase your chance of success in growing rosemary from seed, it is a must for you to get high quality seed. In addition, you need to germinate as many seeds as possible. From the seeds that you try to germinate, only a few of them will sprout. Moreover, you can improve the germination rate by soaking the seed in water for a day.

Other things you need to prepare are a seed tray, a heat mat, and high quality seed starting mix.  When you have everything ready, you can start the process of germinating rosemary seed. It is recommended to do it indoors so that you can control the temperature easily and have the seedlings ready when the weather is warm enough.

To germinate the rosemary seed, you can do these steps.

  1. Fill in the seed tray with seed starting mix.
  2. Place the seeds on each cell and sprinkle it with seed starting mix.
  3. Mist the soil and keep the soil moist until the seeds germinate.
  4. Set the heat mat so that the temperature of the soil is between 27oC and 32o
  5. Wait until the seeds germinate.

2. Preparation

When you are waiting for the seed to germinate, you can prepare the pots. It is recommended to grow the young plants in pots in the first year. Therefore, you can protect them from the cold in winter easily.

At this stage of growing rosemary from seed, you need to have 20 cm deep pots and high quality potting mix. The pots must have drainage holes. In addition, you can add a layer of pebbles at the bottoms of the pots.

3. Transplanting

When the seedlings emerge, you need to mist the soil regularly. In addition, you need to make sure that thy get 6 to 8 hours of light. The seedlings can be placed near a window or under a grow light.

You must transplant the seedlings to the pots when they are 10 cm tall. Before you grow them outdoors, you need to harden the seedling off for a week or two. Therefore, they will be able to adapt to the outdoor environment. Next, you must place the pots in a sunny spot. In their second year, you can plant them directly to the ground.

4. Caring

To maintain rosemary bushes, you need to water them when the soil is dry. In addition, you must add 10-10-10 fertilizer in the spring. It is also important to prune the shrubs by removing 1/3 of their size. The best time to prune them is in the string to midsummer.

Your rosemary bushes will need a kind of protection in the winter. A potted rosemary bush can be put indoors during the winter. However, if you grow rosemary in the ground you need to mulch the soil.

5. Harvesting

The best thing about growing rosemary bushes is it allows you to have aromatic leaves anytime you want. To harvest rosemary leaves, you need to wait until the plants are established. If you want to get the best rosemary leaves, you must harvest the young leaves and stem.

You can harvest 1/3 of each shrub. But, after that, you need to give the plants time to grow. In the fall, you had better harvest only small amount of leaves because the plants are getting ready for the winter.

Growing Rosemary from Cuttings


When your rosemary is mature enough, it can be propagated from stem cuttings. This type of propagation has its own challenge compared to growing rosemary from seed. But, some people prefer to propagate rosemary from stem cuttings because it takes less time. This propagation must be done after the plant blooms.

1. Getting started

In this process, you need to select a healthy rosemary bush. In addition, you must prepare the pots and media. Having 15-cm pots with excellent drainage is a must. Meanwhile, the media must be loose and well-drained. You can use garden soil if it meets the criteria.

2. Cutting

Choose some woody stems. After that, cut 15 cm of the stems from their ends. In order to increase your success, you can apply rooting hormone at the end of the cuts. Moreover, you need to remove the lower half leaves.

Next, you can plant the cuts in the prepared pots. Moist the soil and put them in a sheltered area. Make sure that they get morning sun every day. As an alternative, you can place the pots indoors, near a window, if the weather is not ideal.

3. Transplanting

When the stem cuttings are 8 weeks old, you can transplant them in your garden. For indoor cuttings, you must harden them off for one or two weeks before transplanting them.

Tips on Growing Rosemary from Seed


The rosemary bush is not the easiest plant to grow considering the seed’s slow germination. However, you can have better result in growing rosemary from seed if you follow these tips.

1. Start early

Since rosemary seeds take weeks to germinate, it is recommended to start growing rosemary from seed indoors early in the season. The best time to do it is 8 to 10 weeks before the last spring frost in your area. Therefore, when the weather is warm enough, you already have seedlings to transplant.

2. Mix the soil with sand

Rosemary root is very sensitive to moisture. It will suffer from root rot if the plant grows on soil with bad drainage. To improve the drainage of the soil, you can mix your garden soil with sand.

3. Growing rosemary in containers

This herb grows well in containers. In addition, it offers some advantages. One of them is that you can bring the plant indoors in winter.

4. Space the plant properly

When you are growing rosemary from seeds, you must remember to space the seedlings properly during the transplantation. Proper spacing will provide good air circulation so that the plant can avoid powdery mildew. The recommended space is 45 cm apart between plants and 1.2 m apart between rows.



If you have decided to try growing rosemary from seed, you need to consider which cultivars to grow.

1. Prostratus

This creeping rosemary can make your garden looks beautiful, especially when they are flowering. It is best planted on raised beds, containers, rockeries, and over fences. You can grow them in USDA hardiness zone 7 to 11.

2. Chef’s Choice

This compact variety is perfect for a small kitchen garden. The plant is only 30 to 45 cm tall. Therefore, you can grow it in pots without difficulty. Chef’s Choice is hardy in zone 7 to 10.

3. Tuscan Blue

This variety can grow up to 1.8 m tall. It is dense and has lots of branches. The plant is only grows well in zone 8. Tuscan Blue is perfect as borders or hedges.

3. ARP

If you live in northern area, you can choose ARP rosemary. This plant has excellent cold hardiness. You can plant in in USDA hardiness zones 6 to 10. ARP can reach 1.5 cm in height.

Growing rosemary from seed can take more time, but it is fun. If you provide the right temperature, soil, and moisture for the seeds to germinate, you will be able to get several seedlings in a couple of weeks. However, you must not expect all the seeds to germinate due to their low germination rate.

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