How to Grow Thyme Indoors
Sunlight
Thyme is a well-known sun lover preferring to be planted or placed in a location with access to full sunlight nearly all day long. A bright windowsill that receives eight hours of sun per day is ideal, but if your home is rather shaded or you’re looking to keep your thyme thriving through the darker winter months, a snug spot under some florescent grow lights will work too.
Temperature and Humidity
Thyme is native to the Mediterranean region, and it will thrive best in a hot, arid climate. As best you can, strive to maintain temperatures in your home between 60 and 80 degrees Fahrenheit, taking care to keep humidity to a minimum (that means keeping your plant away from rooms that tend to be more humid like kitchens or bathrooms).
Watering
Once established, thyme plants are drought-resistant and often prefer to be under-watered rather than over-watered. Wait until the soil is completely dry, then saturate your thyme plant, allowing it to dry out again completely before giving it another watering. Keep in mind that thyme will flower, but unlike other herbs, this is not a sign of overwatering or bolting—it will continue to thrive beyond blooming if you trim it back to promote new growth.
Fertilizer
How’s this for simple: Thyme actually prefers soil that lacks nutrients, so supplemental fertilizing is not necessary. This also means that the herb is best planted in a pot or container by itself because combining it with other herbs will likely make the soil too rich for it to thrive properly. If you do want to give your thyme a boost, feed it with a diluted liquid fertilizer early on in its growing season—choose an organic fertilizer if you hope to cook with or eat your herb. Pay close attention to the fertilizer packaging to ensure you add just enough to help, not hurt, your thyme plants.
Pruning and Maintenance
Like outdoor plants, indoor thyme plants can be harvested at any time once they are established. Simply snip off the stems any time you need the herb for a recipe. Potted plants can become woody after three or four years, at which time you should remove, separate, and replant the smaller pieces in separate pots and fresh potting mix.
Container and Size
Thyme doesn’t need much room to grow, so a container as small as four inches in diameter can be enough room to grow young plants. Clay or terracotta pots might work best for this plant. Make sure the container has good drainage.
Potting Soil and Drainage
Soil is perhaps the most important element when trying to grow thyme successfully. Select a soil mixture that is very dry and well-draining, as thyme is particularly susceptible to root rot and overwatering. Sandy mixtures are your best bet—if you choose to use potting soil you already have at home, cut it with a bit of gritty sand or gravel to ensure water moves through the soil quickly. A pot with ample drainage is also important, and those made of clay or terracotta can be beneficial in wicking away extra moisture from the soil. Thyme is not too particular about soil pH levels—it can thrive in a wide range of pH values ranging from 6.0 to 8.0.
Potting and Repotting
When a thyme plant begins to develop woody stems more than tender leaves and shoots, it’s time to repot the plant. Carefully remove it from its container, then separate the pieces of the root. Choose the smaller pieces for transplanting into new pots. Choose small pot about four inches in diameter. Repot the plants with the proper mixture of potting soil, as described above.
Moving Thyme Outdoors for the Summer
Thyme thrives in full sun and makes an excellent outdoor plant. Move the pot outside when the temperature is consistently pleasant at 60 degrees Fahrenheit or above.
Considerations
Thyme grown in containers can become tall, so place it in an area where high winds won’t knock it over. Watch for pests throughout the growing season and treat them appropriately if they happen to show up. Becuse this is a culinary plant, use only organic treatments.
When to Bring Thyme Back Inside
Thyme loves a climate that mimics that of the Mediterranean, so bring it inside when the temperature drops enough to bring a bit of a chill. As a general rule of thumb, bring thyme plants indoors onto a sunny windowsill when the temperatures drop to around 60 degrees Fahrenheit.
