Propagating thyme: cuttings, seeds & division

Natascha
Natascha
Natascha
Natascha

As a child, I played every day in the garden in front of my house in my home town of Rheinlandpflanz. There, my interest in nature grew, as did my aspirations to become a natural scientist. I now study horticultural phytotechnology and am currently writing my bachelor’s thesis on the topic of crop protection in orchards. Since living Berlin, I have become particularly interested in improving the quality of life in cities with the help of plants.

Favourite fruit: figs, passion fruit, berries, limes and oranges.
Favourite vegetables: potatoes, garlic, tomatoes, pickles, lamb’s lettuce and rocket.

Thyme makes a popular addition to any garden, windowsill or kitchen. This hardy and low-maintenance plant is also very easy to propagate in a variety of ways.

Thyme shrub growing outdoors
Propagating thyme is possible from seed, cuttings or division [Photo: Insanet/Shutterstock.com]

Common Thyme (Thymus vulgaris) is an easy to care for and robust shrub. If you would like for your thyme crop to multiply, it is quite easy to do so without buying new seedlings. Here we present several methods for propagating thyme.

Propagating thyme from seed

With a little patience, it is possible to grow thyme from seed, with either those that you have harvested yourself or seeds bought from a shop. Purchased seeds are much more reliable and your best choice to grow thyme from seed. Self-harvested thyme seeds may grow into plants which are quite different from the mother plant, as thyme interbreeds very easily. You can of course sow your own self-harvested seeds if you do not necessarily want a true or particular variety of thyme. Of the 3 ways of propagating thyme presented in this article, from seed is the least straightforward. The following steps will help you to grow thyme from seed should you like to give it a go: 

  • Sowing thyme: Sow seeds indoors at the end of February or in-situ from April.
  • Substrate: A specialist seedling substrate is required here, such as our Plantura Organic Herb & Seedling Compost. Its low nutrients and good structure encourage young seedlings to grow strong and healthy roots.
  • Fill a propagation tray with the substrate, press the soil down well and water with a spray bottle.
  • Scatter the fine seeds evenly over the moistened soil.
  • The seeds can be gently pushed down, but you should not plant thyme seeds deeply or cover them with soil as thyme requires light for germination.
  • Covering the propagation tray with a see-through film or plastic lid will create an optimal humid environment in which the seeds can germinate. Place the tray in a warm, light place which is protected from direct sunlight.
  • At a temperature of around 16 °C, the first seedlings should begin to appear after 2 weeks, although this could take up to 3 or 4 weeks.
  • During this time, it is important to keep the substrate moist and to ventilate the propagation tray each day for a few minutes.
  • As soon as the seedlings are visible, the plastic cover can be removed. After about 4 to 5 weeks, the thyme seedlings can be pricked out and planted in threes or fours in larger pots.
  • The plantlets may take a little time to acclimatise to the unprotected conditions outside of the propagation tray.

Tip: Mix the fine seeds with sand at a ratio of 1:1. This helps to distribute evenly when you are sowing your thyme seeds.

Organic Herb & Seedling Compost, 20L
Organic Herb & Seedling Compost, 20L
  • Perfect for herbs as well as sowing, propagating & transplanting
  • For aromatic herbs & healthy seedlings with strong roots
  • Peat-free & organic soil: CO2-saving composition

Propagating thyme from cuttings

Thyme propagates easily from cuttings. This method is particularly good for true-to-type propagation as it produces clones of the mother plant. Here we have put together a step-by-step guide for how to propagate thyme from cuttings:

  • Propagating from cuttings is, in principle, possible throughout the entire year. However, it is best to do so in the growing season during the spring and summer.
  • Choose a suitable growing medium, such as our Plantura Organic Herb & Seedling Compost. Mix in a third sand to make the soil even more permeable and an additional handful of composted material as a starter fertiliser.
  • Suitable cuttings are healthy, young, non-woody shoots which have not yet flowered.
  • Using a sharp knife, cut the sprigs to a length of 5 to 8 cm, directly under a leaf base or node.
  • Remove the leaves from the lower half of the shoots and plant the cuttings individually.
  • To do so, fill small planting pots with the substrate and create a planting hole with a pencil, into which you can plant the cutting. Press the soil around the cutting firmly and then water.
  • A temperature of around 20 °C, high humidity, no direct sunlight and regular watering will ensure the optimal conditions for good rooting.
  • When the cuttings have developed new roots, they can be planted out in the garden or in a larger pot. It takes around 6 to 8 weeks for new roots to form.

Tip: Propagation by layering is even easier. Here, a shoot is simply bent over so that it makes contact with the ground. It is held in place there with, for example, a wire hanger or stone. If you are lucky, roots will form after 3 to 4 months, at which time the offshoot can be separated from the mother plant and moved to a new location.

Dividing thyme

In the case of old and very woody thyme plants, it is best to propagate them by division. In this way, a plant that is no longer active or vigorously growing can be divided in order to grow into many small and healthy thyme plants. After 3 to 4 years thyme begins to enter senescence – at this point it is time to divide it. It is best to do so in the spring, allowing the new thyme plants to establish themselves in their new location before winter. With a little luck, they will bloom right away.

First, carefully dig up the old thyme plant, including the rootstock, being careful not to damage any roots. Remove any diseased parts of the plant as well as the middle section, which is old and woody. With the help of a spade, shovel or a clean, sharp knife, divide the rest of the thyme bush into smaller plants, each with its own root system. Now you can replant the thyme plants, around 30 cm apart from one another, and water them well. You can read more about how to care for thyme in our special article.

Now you have read about how to propagate thyme and to multiply your crop, why not read our dedicated article about the benefits and uses of thyme.

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