Thyme (Thymus vulgaris) is a low-growing, woody perennial that performs especially well in somewhat dry, sunny conditions. A beloved Mediterranean herb, it holds its taste in cooking and blends well with other flavors of its native region, such as garlic, olive oil, and tomatoes.
The tiny pink, lavender, or white tubular flowers of thyme plants appear in the spring and summer months and are well-liked by bees and other pollinators. Its tiny gray-green leaves remain evergreen, and most thyme varieties can even be harvested in winter in the zones where it is a perennial.
Thyme can be planted at almost any time. It will mature enough to allow for harvest within a few months, then will reliably return year after year in USDA zones 5 through 9 where it is hardy. Providing a thick layer of mulch in colder regions helps protect thyme during the winter.
|Common Name||Thyme, Common Thyme, Garden Thyme, English Thyme|
|Botanical Name||Thymus vulgaris|
|Plant Type||Herbaceous perennial|
|Mature Size||6-12 in. tall, 6-12-in. wide|
|Sun Exposure||Full sun|
|Soil Type||Loamy, sandy|
|Soil pH||Acidic to alkaline|
|Bloom Time||Spring, Summer|
|Flower Color||Pink, Purple, White|
|Hardiness Zones||5–9 (USDA)|
Thyme is a widely adaptable herb, making it a great option for beginner gardeners who are looking to foster a kitchen garden. Here are the main requirements for growing thyme:
- Plant in a spot that gets full sunlight—at least six to eight hours of bright light daily.
- Maintain a soil environment that is no overly rich or moist.
- Water plants only occasionally, allowing the plant's soil to dry completely in between waterings.
- Feed thyme plants each spring with an all-purpose, balanced fertilizer that's been diluted to half-strength.
Thanks to their Mediterranean origins, thyme plants thrive best in full sunlight, in a spot where they can receive between six and eight hours of light daily. Plant them in a sunny, exposed spot in your garden, or in decorative planters that can be moved around throughout the day to chase the light. If you're growing a thyme plant indoors, place it on a sunny windowsill or, even better, in a room that catches a lot of rays throughout the day, such as a sunroom.
The worse your soil is, the better your thyme plant may grow. The easy-going herb prefers sandy or loamy soil instead of moist soil, and can even thrive in rocky gravel. If you're planting your thyme in containers, opting for a clay or terracotta pot can be helpful—the absorbent material will wick away additional moisture from the soil and help create the right environment for your thyme. No matter what, make sure your soil is well-draining, as thyme is temperamental about wet feet.
To properly nurture your thyme plant, water established plants only occasionally—every other week or even once a month should suffice, depending on your outdoor climate. You should wait until the soil is completely dry, then water to saturation, then allow it to dry out again. Thyme is also drought-resistant, so don't fret if you go an extra few days without giving it water. However, pamper young plants a bit more, checking water more frequently until roots are well established.
Temperature and Humidity
Thyme plants have no special needs when it comes to temperature and humidity and can thrive through most months of the year until there is frost, at which point they will go dormant for the winter. That being said, their largest period of growth is undoubtedly throughout the summer months—this is also when you'll notice their flowers in bloom, which will attract bees and various other insects. Thyme needs good air circulation—especially in warm, humid climates—to avoid fungal diseases, so space plants out well to ensure good airflow.
Treat thyme plants each spring with an all-purpose fertilizer diluted to half-strength. Keeping the fertilizer at half-strength will ensure the plant doesn't produce too much foliage, which can dilute its fragrant oils and, thus, its flavor.
Types of Thyme
If you want something a little different from common thyme (T. vulgaris), here are a few varieties often planted:
- Golden lemon thyme (Thymus x citriodorus 'Aureus'): This thyme has a true lemon scent in addition to the minty quality of thyme and boasts golden, variegated leaves.
- Woolly thyme (Thymus pseudolanuginosus): This variety grows as a soft, flat spreading carpet and cascades nicely in rock gardens. Because it has no scent, it's not used for cooking and is instead relied on for landscape purposes, like growing in patio cracks.
- Caraway thyme (Thymus herba-barona): This varietal is low-growing, with pale pink flowers and the scent of caraway.
- Creeping thyme (Thymus praecox): True to its name, this variety grows as a low mat, only two to three inches tall, with pink, magenta, lavender, or white flowers. It's often used as a ground cover.
Once established, thyme plants can be harvested at any time, as the flavor of the herb is retained even after flowering. That being said, the flavor will be strongest just before the plant flowers, so that is typically the best time to make your cuttings. To harvest, simply snip a few stems any time the inspiration to cook with the herb hits. Do not harvest more than one-third of the plant at one time; generally, you'll get two to three crops out of a single plant per season.
Fresh thyme can be stored in the refrigerator for one two to weeks and should be removed from the woody stem before use. Alternatively, you can dry your thyme by hanging it upside down in a warm, dark place or dehydrating it slowly in an oven. The dried thyme can then be crushed before use and will last up to a year or more with proper storage.
Thyme is rather difficult to grow from seeds, so the more common method is to take stem cuttings and root them. Propagating thyme via stem cuttings should be done in the late spring, using a "mother" plant that has established growth of at least a few seasons. Here is how to propagate thyme through stem cuttings:
- Using sharp, clean pruners, clip a stem around 3 inches in length from a part of the plant that is well-established and not too woody. The stems should have plenty of new green growth, but the lower part of the stem can be more mature.
- Remove all but two or three sets of leaves from the cutting (at the top). You can dip the cut end of the stem into a rooting hormone to help boost success if you prefer, but it's not necessary.
- Plant the cutting in a container filled with ordinary potting soil mixed with sand or perlite. The soil should be moist but not soaked.
- Set the container in a location with bright indirect light and keep the soil moist until new growth begins.
- After six weeks or so, the cutting will develop a root system sufficient enough to allow it to be transplanted into a larger container or into your garden.
Potting and Repotting Thyme
Like many culinary herbs, thyme is a great candidate for container gardening, thanks to its modest size, appealing flowers, and hearty nature. Because thyme has a relatively sprawling and sturdy root system, you should opt for a slightly larger pot for your thyme plant—at least one gallon or larger to start. Containers made from natural materials, like terracotta or clay, are preferred, as they'll naturally wick away excess moisture from the plant's soil, preventing your thyme from getting root rot or wet feet. You should also make sure your container has ample drainage holes at its base.
Fill your chosen container with a quality potting mixture that's been amended with a bit of sand or perlite to help with drainage. Place your thyme in the container, ensuring that the root ball is located just at the soil line—bury it too deep, and your thyme could rot. Water the plant immediately after planting, then only as the top 2 to 3 inches of soil dries out. Locate the plant somewhere where it can get full sunlight for at least six to eight hours per day.
Common Problems With Thyme
Thyme is a very durable plant all things considered, so it's not likely that you'll run into too many issues when growing this culinary herb. That being said, here is how to combat a few common problems.
Leaves Turning Brown
If you notice your thyme plant has leaves that are browning, dropping, or wilted, root rot is likely to blame. Thyme plants are very sensitive to too much moisture and will react poorly if overwatered even for a few weeks. If you notice symptoms of overwatering or root rot with your thyme plant, dial back the frequency with which you water the plant. If that doesn't work, you can uproot the plant from its container (or the ground), snip back any roots that look brown or rotten, then replant the thyme in fresh soil that has been amended with sand or perlite.
Leaves Turning Yellow
While yellowing leaves on your thyme can be yet another signal that it's suffering from root rot, it can also be an indication that your plant is receiving too much nitrogen. Other signs of excess nitrogen include a leggy plant or a too-mild flavor. If you've ruled out signs of overwatering, it's possible that your soil is actually too fertile for this adaptable plant. Test your soil to determine its concentration and replant it in a container with new soil if necessary.
Leaves That Are Drying Out
Thyme plants will only live for about five or six years, and one of the biggest indications that they're reaching their expiration date is the presence of crispy, dried leaves. If you noticed a considerable amount of foliage drying up or falling from the plant, it's time to take cuttings from the plant to propagate and work on expanding your collection before phasing your current plant out.
How long can thyme live?
With proper care, thyme can live up to five or six years in the right environment. That being said, you will notice a decline in growth, fullness, and fragrance a the years progress, so it's a good idea to consistently take cuttings from your plants in order to keep your thyme plant population robust.
Can I use thyme as a lawn cover?
Yes. Thyme—specifically creeping thyme—is often used as a popular ground cover in areas where it may be difficult to grow traditional grass. It will spread quickly, providing a soft-yet-durable mat that requires little upkeep (and even less water).