Thyme in Zone 8A — Southeast

Thyme is a fantastic herb to grow in the Southeast. Its earthy, slightly floral flavor elevates everything from grilled meats to summer vegetables. Plus, it's a perennial, meaning you'll enjoy its fragrant foliage year after year, even with our long summer.

Our hot and humid summers can bring challenges, but with proper timing and attention to soil drainage, you can easily grow thriving Thyme. Our long growing season of around 245 days gives you plenty of time to establish a healthy patch.

Starting Thyme indoors is an option here in the Southeast, but honestly, it's usually easier to buy established transplants. Thyme seeds are tiny and slow to get going, so unless you're after a specific variety, starts are the way to go. However, if you want to try from seed, start in mid January through early February, about eight weeks before you plan to transplant outdoors.

Use seed trays with a good seed-starting mix and provide warmth (a heat mat helps) and plenty of light from a grow light. Bottom watering is ideal – set the tray in a shallow dish of water and let the soil soak it up to avoid disturbing the tiny seeds. Our moderate spring gives you a decent window to get them established before the summer heat kicks in.

Transplant your Thyme seedlings outdoors in mid March through mid April, after the last expected frost. Before transplanting, harden them off by gradually exposing them to outdoor conditions for about a week. This helps them adjust to the sun and wind.

Space your Thyme plants about 8-12 inches apart in a sunny spot with well-drained soil. Keep an eye on the weather forecast – we can still get some chilly nights in early spring, so be ready to cover them if needed. Again, buying starts from a local nursery often saves a full season of waiting, and you'll have a head start on those delicious Thyme-infused dishes.

Direct sowing Thyme is possible in the Southeast, but it takes patience. Sow seeds in mid March through late August, when the soil has warmed up. You'll want to prep the soil well, ensuring it's loose and well-draining.

Sprinkle the tiny seeds thinly over the soil surface and gently press them in. Keep the soil consistently moist, but not waterlogged, until germination. Thin seedlings to 8-12 inches apart once they're large enough to handle. Just remember, direct sowing means a longer wait for your first harvest compared to using transplants.

Thyme is a very drought-tolerant herb, which is a blessing during our long summer months in the Southeast. Overwatering is a much bigger problem than underwatering with this plant, and it can quickly lead to root rot in our humid climate.

A good rule of thumb is to water only when the top two inches of soil feel dry to the touch – use the "finger test." During the hotter parts of the summer, this might mean watering once a week, giving them about ½ inch of water. In the spring and fall, you might only need to water every other week, or even less, especially with our reliable afternoon thunderstorms.

Always water at the base of the plant to avoid wetting the foliage, which can encourage fungal diseases in our humid conditions. Signs of underwatering include wilting or yellowing leaves, while overwatering can cause the leaves to turn brown or black and the plant to become mushy. A light layer of pine straw mulch can help retain some moisture without suffocating the roots, and it's readily available here in the Southeast.

Thyme requires minimal pruning, but a little attention will keep it healthy and productive. After flowering, usually in the late spring or early summer, cut back the stems by about one-third to prevent the plant from becoming woody. Be careful not to cut into the old wood, as this can stunt new growth.

Throughout the growing season, you can also trim off any dead or damaged stems. As first frost approaches in mid- November, give your Thyme a final trim to neaten it up for the winter. This encourages new growth in the spring.

You can start harvesting Thyme sprigs anytime after the plant is established, usually around late May, but the best flavor comes just before flowering. This can continue all the way through late November in our long growing season. Look for healthy, vibrant green stems.

To harvest, simply cut the stems with scissors or pruning shears, leaving at least a few inches of growth on the plant. You can strip the leaves from the stems and use them fresh, or dry the stems for later use. Regular harvesting encourages the plant to produce more foliage, so don't be shy! As the first frost approaches in mid- November, harvest as much as you can and dry it to enjoy throughout the winter.

Here in the Southeast, we face two primary challenges when growing Thyme: root rot from overwatering and fungal diseases due to humidity.

Root Rot

• What it looks like: Yellowing or browning leaves, wilting, and a mushy stem base. The roots themselves will be dark and slimy.
• What causes it: Overwatering, especially in our clay soil, prevents the roots from getting enough oxygen. Our wet-summer rainfall can exacerbate the issue.
• How to fix/prevent it: Ensure your Thyme is planted in well-draining soil. Amend heavy clay soil with compost and consider raised beds. Water only when the top two inches of soil are dry.

Fungal Diseases

• What it looks like: Powdery mildew (white, powdery coating on leaves) or leaf spot (small, dark spots on leaves).
• What causes it: High humidity and poor air circulation create the perfect environment for fungal growth.
• How to fix/prevent it: Plant Thyme in a location with good air circulation and full sun. Avoid overhead watering. If fungal diseases appear, remove affected leaves and consider using a fungicide labeled for herbs.

Southeast Specific Challenges: Our hot heat, humid humidity, and wet-summer rainfall create a perfect storm for root rot and fungal diseases. Be vigilant about watering practices and choose a well-drained location to give your Thyme the best chance to thrive.

Thyme benefits from companion planting, and some of the best companions thrive in our Southeast gardens. Rosemary, sage, and lavender all share similar growing requirements (full sun, well-drained soil) and can even help deter pests. Cabbage benefits from Thyme's pest-repelling properties, while Thyme can improve the flavor of strawberries. Tomatoes also enjoy the company of Thyme, as it can help repel certain pests and improve their overall health.

Avoid planting Thyme near mint. Mint is an aggressive grower and can quickly outcompete Thyme for resources. Plus, mint prefers moist soil, which is the opposite of what Thyme needs.