Updated February 26, 2022 by Mark Marino
Thyme is a Mediterranean herb that is attractive for windowsills as well as great for use in a wide variety of recipes. The herb doesn’t fare well in cold weather, and it prefers to be in dry conditions, so growing thyme indoors is ideal in most climates. It’s a compact plant, so it doesn’t take up much room indoors. You can grow new thyme plants by themselves or as part of an herb garden.
Growing Thyme Indoors
Indoors, you can plant thyme plants as young plants, mature plants or from thyme seeds. Most of the time, people bring mature plants home from a grocery store or big box store to plant them in a plant pot at home. It is also possible to plant them from cuttings of another thyme plant as well as by dividing an existing plant into two or more plants. The potted thyme plants can fit easily in a windowsill where they can soak up the sun. And like other indoor plants, a thyme plant will also help to purify the air and will emit oxygen.
When growing thyme indoors, it’s important to have all of the supplies you need from a garden center so that the job can be done properly. You will need a plant pot, some potting soil, and an area with the right amount of sunlight. Whether you are growing lemon thyme or any other variety, you will need these supplies.
Pots & Potting Soil
For this job, you will need some regular potting soil. It’s preferred if it has some sand in it for drainage. Many commercial potting soils do contain sand, so take a look at the ingredients to see whether it does. Sand allows for well drained soil, and the thyme plant prefers to be on the dryer side.
You also need a plant pot that will accommodate the plant you already have plus some growth. A good pot for growing thyme indoors will have plenty of drainage in it. Look for pots with drainage holes in the bottom that allow for drainage. Many good pots have a large hole for drainage in the center and a built-in plate under the pot. This will keep the windowsill or other spot dry after your thyme has been watered.
If you are transferring an existing plant into a pot, fill the pot with potting soil only part of the way up and with a depression in the middle so that it can accommodate the existing soil. If you are growing from a division or a cutting, fill it to near the top with soil and press the plenty into the soil.
Coming from a dry climate, thyme is a drought-resistant plant that doesn’t need to be watered often. In fact, the soil should thoroughly dry out before it is watered again. To check the soil, put one finger about .5″ into the soil to see whether it’s dry. If it is, it can be watered again. Water it thoroughly, but don’t drown it. If there is a lot of water coming out through the drainage holes, you have overwatered it. If you overwater this plant, it can develop root rot, which is usually fatal to plants.
Thyme plants like a lot of sun, so it’s best to put them in a very sunny area. It likes bright light and direct light, and it needs at least six hours of sunlight every day. Though this is the best scenario for growing thyme, the plant can grow in indirect light if the light is bright enough. You can also grow garden thyme under fluorescent lights, but they would have to stay on for at least 14 hours every day.
When taking care of indoor thyme, it’s done in the same basic ways that outdoor thyme is cared for. Every spring, your thyme plant can use some fertilizer to keep it growing well and getting enough nutrition from the soil. Add some all-purpose fertilizer that has a ratio of 10-10-10, diluting it to half strength. Or, you could add liquid seaweed or fish emulsion, again diluted to half strength. This dilution prevents the thyme plant from growing excess foliage. Extra foliage will make the oils in the thyme plant less potent.
Once the spring starts, cut off the branches under the point where the new growth has begun. Make sure your pruning shears are highly sharp so that the plant won’t have a jagged cut that could let in bacteria. As the summer brings more growth due to more sunlight, you can pinch off growth that is uneven on the plant to get the plant to branch more. If a branch gets overly woody, it can be cut back to allow for new growth. Don’t prune it at all in the fall or winter.
When roots start peaking out from the drainage holes, it’s likely time to repot the plant into a bigger pot. To do this, plant it the way you did it the first time by placing some potting soil in the pot. Then, bring the plant and the soil that clings to it to the new pot and arrange the soil around it. It’s always easier to do this when the soil is dry.
You can harvest thyme when the plant has a lot of foliage. To harvest them, cut off the stems with your sharp pruning shears and rinse them off. You can pull off the leaves easily and use them in your recipes. You can stew the stems to give more flavor to it, but always remember to strain them out once it has cooked. You can add the whole leaves to a number of recipes while others will require you to chop the leaves. If you want to dry the leaves, put them on a regular cookie sheet and keep it in an area that is dry and warm for about one day.
Cooking with Thyme
Fresh thyme and oregano are my favorite fresh herbs. I use fresh thyme in virtually every homemade soup. Chef’s tip: butter-baste pan-seared fish with a sprig of thyme for more aromatics. Finish with fresh lemon juice and take your fish dish to a new level. Thyme is also used in the classic Herb de Provence along with rosemary, savory, oregano, and marjoram.
Indoor Thyme FAQs
Can you grow thyme indoors all year long?
Yes. It can be grown easily inside, and it’s simpler to do so because there is no frost indoors that would cause you to bring them inside.
Can you grow thyme indoors in the winter?
Yes. Thyme plants thrive indoors and have no cold weather to cause them damage.