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How to Grow Thyme

Thyme is an attractive perennial herb that deserves a spot in every herb kitchen garden. With its delightful aroma, and endless uses in cooking, is a true garden gem.

Thyme growing in a terracotta pot.

Growing Thyme Basics

Thyme (Thymus vulgaris) is a perennial evergreen herb that belongs to the Lamiaceae (mint) family. It is a low-growing, woody-stemmed plant that is well-suited for both garden beds and containers.

Thyme can be propagated through various methods, including starting from seeds, cuttings, layering, and division.

Key Characteristics

  • Stems: Woody, slender, and branching, with small leaves
  • Leaves: Small, oval-shaped, gray-green leaves with a slightly furry texture
  • Height: 6 to 12 inches/ 15 to 30 cm
  • Flowers: Tiny, pinkish-purple flowers that bloom in late spring to summer

Growing Conditions

  • Climate: Hardy, able to withstand cold winters; USDA zones 5-9
  • Soil: Well-drained, sandy, or loamy soil; pH 6.0-8.0
  • Sunlight: Full sun, at least 6 hours of direct sunlight per day
  • Watering: Drought-tolerant; water deeply but infrequently, allowing soil to dry between watering
  • Fertilization: Minimal fertilization needed; apply a light, balanced fertilizer in spring if desired
  • Planting Time: Plant in spring or fall, spacing plants 12 to 24 inches/ 30 to 60 cm apart
  • Harvest: Harvest leaves as needed throughout the growing season; more frequent harvesting encourages bushier growth
  • Pruning: Prune back woody stems in early spring to promote new growth and maintain shape

Thyme varieties

There are numerous varieties of thyme available, each with its own unique flavor, aroma, and growth habit. Most thyme varieties are relatively hardy and can adapt to a range of climates. However, some varieties may be better suited to warmer or cooler climates.

Some popular culinary thyme varieties include:

  • Common Thyme (Thymus vulgaris): The most widely grown variety, known for its strong, classic thyme flavor. It is used in a wide range of culinary dishes, including soups, stews, and meat dishes. This variety is hardy and can grow well in both cool and warm climates.
  • Lemon Thyme (Thymus x citriodorus): As the name suggests, this variety has a distinct lemon scent and flavor. It is a great addition to fish dishes, marinades, and herbal teas. Lemon thyme is slightly less hardy than common thyme and may require some winter protection in cooler climates (USDA zones 7-9).
  • Caraway Thyme (Thymus herba-barona): This variety has a subtle caraway flavor. It is well-suited to cooler climates and can tolerate some shade.
  • Creeping Thyme (Thymus serpyllum): A low-growing, spreading variety that is often used as a fragrant groundcover or planted between stepping stones. It has a milder flavor compared to common thyme. Creeping thyme is hardy and can tolerate a wide range of temperatures, making it suitable for both cool and warm climates.
  • Silver Thyme (Thymus argenteus): Prized for its attractive, silver-edged foliage, this variety is both ornamental and flavorful. It is used in cooking and adds a decorative touch to gardens. Silver thyme is best suited to warmer climates (USDA zones 8-10) and may require some winter protection in cooler areas.
  • English Thyme (Thymus ‘Broad Leaf English’): A classic variety with a strong, savory flavor, often used in traditional English cooking, including in stews, soups, and roasted meats. This variety is hardy and can grow well in both cool and warm climates.

When to plant thyme

The best time to plant thyme depends on your local climate and whether you are starting from seeds, seedlings, or divisions.

If starting from seeds, you can begin the process indoors 6 to 8 weeks before the last expected frost date in your area. Once the seedlings have developed a few sets of true leaves and the risk of frost has passed, you can transplant them outdoors.

If you are transplanting seedlings or divisions from an established plant, the best time to plant them is in the spring or early fall to allow the plants to establish their roots before the extreme temperatures of summer or winter:

  • In regions with mild winters (USDA zones 8-10), you can plant thyme in the fall, giving the plants time to establish themselves before winter.
  • In colder regions, fall planting is not recommended, as the plants may not have enough time to develop a strong root system before the cold weather sets in.

Where to plant thyme

When choosing where to plant your thyme, take the following into account:

  1. Sun Exposure: Thyme grows best in full sun, meaning it needs at least 6 hours of direct sunlight per day. Choose a spot in your garden that receives plenty of sunlight, such as a south-facing slope or a raised bed.
  2. Soil: Thyme prefers well-draining soil that is slightly dry and not overly rich. The ideal soil pH range for thyme is between 6.0 and 8.0. If you have heavy clay soil, consider amending it with sand, gravel, or organic matter to improve drainage. Alternatively, you can plant thyme in raised beds or containers with a well-draining potting mix.
  3. Spacing: When planting thyme, space the plants 12 to 24 inches/ 30 to 60 cm apart, depending on the variety. This allows for proper air circulation and prevents the plants from becoming overcrowded.
  4. Companion Planting: Thyme is a good companion plant for many vegetables and herbs. It can help repel pests like cabbage worms, whiteflies, and tomato hornworms. Consider planting thyme near vegetables such as cabbage, broccoli, tomatoes, and eggplants.
  5. Container Planting: If you have limited garden space or live in a region with poor soil, thyme can be successfully grown in containers. Choose a pot at least 6 inches/ 15 cm deep with generous drainage holes, and use a well-draining potting mix.

Growing thyme from seed

Starting thyme from seeds is an economical way to grow a large number of plants. You can either start the seeds indoors or sow them directly outdoors, depending on your local climate and the length of your growing season.

Starting seeds indoors

  • Sow the seeds indoors 6 to 8 weeks before the last expected frost date.
  • Use a well-draining seed starting mix and sow the seeds on the surface, lightly covering them with a thin layer of the mix.
  • Keep the soil moist and maintain a temperature of around 60-70°F/ 15-21°C until germination occurs, which can take 14-28 days.
  • Once the seedlings have developed a few sets of true leaves, transplant them into individual pots and grow them until they are ready to be planted outdoors after the risk of frost has passed.

Tip: Thyme seeds are delicate; they need to be barely covered or left on the soil surface for best results.

Sowing direct

Alternatively, in regions with long growing seasons, you can sow thyme seeds directly outdoors in the spring or early summer.

  • Prepare a well-draining seed bed in a sunny location and sow the seeds thinly on the surface, lightly raking them into the soil.
  • Keep the soil moist until germination occurs.
  • Thin the seedlings to 12-24 inches/ 30-60 cm apart once they have developed a few sets of true leaves.

Other methods to propagate thyme

Cuttings

Propagating thyme from cuttings is a quick and reliable method to create new plants.

  • In late spring or early summer, take 4-6 inch/ 10-15 cm cuttings from the soft, new growth of a healthy thyme plant.
  • Remove the lower leaves and dip the cut end in rooting hormone (optional).
  • Plant the cuttings in a well-draining potting mix, keeping the soil moist but not soggy.
  • Place the cuttings in a bright, warm location out of direct sunlight until they develop roots, which usually takes 4-6 weeks.
  • Once the cuttings have rooted, transplant them into individual pots or directly into the garden.

Layering

  • In spring or early summer, select a long, flexible stem and remove the leaves from the portion that will touch the ground.
  • Gently bend the stem to the ground and secure it with a U-shaped wire or pin, covering the leafless portion with soil.
  • Keep the soil moist and leave the stem attached to the parent plant until it develops roots, which usually takes 6-8 weeks.
  • Once rooted, sever the stem from the parent plant and transplant the new plant to its permanent location.

Division

  • Thyme plants can be divided every 3-4 years to rejuvenate the plant and create new ones.
  • In early spring or fall, carefully dig up the entire plant and gently separate it into smaller sections, ensuring each division has a portion of roots and foliage.
  • Replant the divisions in well-draining soil, water them well, and keep them moist until they establish themselves.

Transplanting thyme

The best time to transplant thyme is in the spring or early fall, when temperatures are mild and the plant is not under stress from extreme heat or cold. Avoid transplanting during the peak of summer, as this can cause undue stress to the plant.

Hardening Off

Before transplanting your thyme plants outdoors, it’s essential to harden them off to minimize transplant shock.

Start by placing the plants outdoors in a sheltered location for a few hours each day, gradually increasing the duration and exposure to direct sunlight over a period of 7-14 days.

Preparing the planting site

When you are ready to put the plants in the ground:

  • Choose a sunny location with well-draining soil. If necessary, amend the soil with organic matter, such as compost, to improve drainage and fertility.
  • Clear the area of weeds and debris to minimize competition for nutrients and water.
  • Dig holes that are slightly larger than the root ball of your thyme plants. When transplanting multiple thyme plants, space them 12 to 24 inches (30 to 60 cm) apart to allow for proper air circulation and room for growth.

Transplanting

  1. Carefully remove the thyme plant from its container or gently lift it from the ground, taking care to keep the root ball intact.
  2. Place the plant in the prepared hole, ensuring that the top of the root ball is level with the surrounding soil surface.
  3. Backfill the hole with soil, gently firming it around the plant to eliminate air pockets.
  4. Water the plant thoroughly to help settle the soil around the roots and promote good contact between the roots and the soil.

Protect the newly transplanted thyme from extreme weather conditions, such as strong winds or excessive heat, by providing temporary shade or shelter if necessary.

Once your thyme plants are established, they will be relatively low-maintenance and drought-tolerant.

Thyme plant care and maintenance

Thyme is a relatively low-maintenance herb that can thrive with minimal care once established. However, to ensure your thyme plants remain healthy and productive, follow these care and maintenance guidelines:

Watering

Thyme is drought-tolerant and prefers well-draining soil. Water your plants deeply but infrequently, allowing the soil to dry out between watering sessions. Avoid overwatering, as this can lead to root rot and other fungal diseases. In most cases, thyme plants will require watering once or twice a week, depending on your local climate and soil conditions.

Fertilizing

Thyme does not require frequent fertilization, as it grows best in lean, slightly dry soil. If desired, you can apply a light, balanced, organic fertilizer once in early spring to support healthy growth. Avoid over-fertilizing, as this can result in excessive foliage growth at the expense of flavor.

Pruning and harvesting

Regular pruning and harvesting help maintain the shape of your thyme plants and encourage bushier, more compact growth.

Trim back the plants by about one-third in early spring before new growth emerges. Throughout the growing season, harvest thyme leaves as needed for culinary use, removing no more than one-third of the plant at a time.

After flowering, cut the stems back to promote fresh growth and prevent the plants from becoming woody.

>> More information: How to Harvest Thyme

Overwintering

Thyme is a hardy perennial that can survive cold winters, especially if you are growing a cultivar suited to your climate.

In colder regions (USDA zones 5-7), provide winter protection by applying a layer of organic mulch around the base of the plants after the ground has frozen. In areas with severe winters, you may need to cover the plants with a frost cloth or other protective material.

Propagation

Every 3-4 years, consider dividing your thyme plants in the spring or fall to rejuvenate them and control their size. Carefully dig up the plants, separate them into smaller sections, and replant them in well-draining soil. This process also allows you to create new plants for your garden or to share with others.

Thyme growing in a pot.

Troubleshooting common problems

While thyme is generally a low-maintenance and problem-free herb, it can sometimes experience issues. Here are some common problems and how to address them:

Yellowing or wilting leaves

Yellowing or wilting leaves can indicate several issues, such as overwatering, underwatering, or nutrient deficiencies.

Check the soil moisture and adjust your watering schedule accordingly. Ensure the plant is receiving enough sunlight and that the soil is well-draining.

If the problem persists, consider applying a balanced, organic fertilizer to address any nutrient deficiencies.

Root rot

Root rot is a fungal disease that can occur when thyme is planted in poorly draining soil or overwatered. Symptoms include yellowing, wilting leaves and a foul smell emanating from the soil.

To prevent root rot, ensure your thyme is planted in well-draining soil and avoid overwatering. If root rot is suspected, remove the affected plant and improve soil drainage before replanting.

Powdery mildew

Powdery mildew is a fungal disease that appears as a white, powdery coating on the leaves and stems of thyme plants. It thrives in humid conditions with poor air circulation.

To manage powdery mildew, improve air circulation by pruning congested growth and ensure the plant receives adequate sunlight. Remove affected leaves and apply a fungicide, such as neem oil or sulfur, if the problem persists.

Spider mites

Spider mites are tiny arachnids that can infest thyme plants, causing stippling or yellowing of the leaves and the presence of fine webbing. These pests thrive in hot, dry conditions.

To control spider mites, regularly mist the foliage to increase humidity and dislodge the mites. You can also use insecticidal soap or neem oil to manage infestations.

Aphids

Aphids are small, sap-sucking insects that can cause distorted growth and sticky honeydew on thyme plants.

To control aphids, blast them off the plant with a strong jet of water or apply insecticidal soap.

Encouraging beneficial insects, such as ladybugs and lacewings, can also help control aphid populations.

Woody or leggy growth

Thyme plants can become woody or leggy over time, resulting in reduced leaf production and flavor.

To prevent this, regularly prune your thyme plants, removing woody stems and encouraging fresh, compact growth. Every 3-4 years, consider dividing the plants to rejuvenate them.

Cold damage

In regions with severe winters, thyme plants may experience cold damage, leading to browning or dieback of foliage.

To protect your plants, apply a layer of organic mulch around the base after the ground has frozen, and cover the plants with a frost cloth or other protective material during extreme cold spells.