Lavender in Zone 6B — Southeast

Lavender is a fantastic addition to any Southeast garden. Its fragrant blooms and calming scent make it perfect for teas, crafts, and even culinary dishes. Plus, the satisfaction of growing your own herbs in our long summer is hard to beat.

While our hot and humid summers can present challenges, especially with fungal diseases, you can absolutely grow lavender here with careful planning. Our 208-day growing season gives you plenty of time to get it established, as long as you pay attention to drainage and airflow.

Starting lavender from seed indoors is possible, but it can be a slow process. If you're up for the challenge, begin in early to late February, giving the seedlings about 10 weeks to grow before transplanting.

Use seed trays with a well-draining seed-starting mix. Keep the soil consistently moist, but not soggy, by watering from the bottom. Place the trays in a warm location with plenty of light. Remember that our spring weather can still be cool, so a heat mat can be helpful.

Transplant your lavender seedlings outdoors from mid April through early May. Before planting, harden them off by gradually exposing them to outdoor conditions for about a week.

Choose a sunny spot with well-drained soil, spacing the plants 12-18 inches apart. Honestly, in our clay soil, buying established starts from a local nursery is often a much easier path to success.

Lavender thrives on neglect, and in the Southeast, less is definitely more when it comes to watering. Our hot, humid summers and regular afternoon thunderstorms mean that overwatering is a bigger threat than underwatering.

During the first few weeks after transplanting, water regularly to help the plants establish. Once established, water only when the top 2 inches of soil are dry to the touch – use the "finger test." Usually, about 1 inch of water per week, including rainfall, is plenty. Always water at the base of the plant to avoid wetting the foliage and encouraging fungal diseases in our humid climate.

Signs of underwatering include wilting or drooping leaves. Overwatering can lead to yellowing leaves and, eventually, root rot. A light mulch of gravel or pine straw can help improve drainage and prevent soil from splashing onto the leaves, but don't overdo it.

Pruning lavender is essential for maintaining its shape and encouraging new growth. After the first flush of flowers in late summer, deadhead the spent blooms and lightly shape the plant into a mound.

Cut back about 1/3 of the plant's growth, but be careful not to cut into the old wood, as it won't regrow. In late October, after the first frost, you can give the plant a light trim to remove any dead or damaged foliage.

You can typically expect your first lavender harvest from mid July through late August in the Southeast. The best time to harvest is in the morning, after the dew has dried but before the sun gets too hot.

Look for flower stems where the buds are showing color but haven't fully opened yet. Cut the stems long, leaving several inches of foliage on the plant. To dry the lavender, bundle the stems together and hang them upside down in a cool, dark, and well-ventilated place. Regular harvesting encourages the plant to produce more blooms throughout our long summer. As the first frost approaches in late October, harvest any remaining blooms to enjoy indoors.

Lavender can face a few challenges in our Southeast climate. Here are some common issues and how to address them:

• Root Rot:
• What it looks like: Yellowing leaves, wilting, and a general decline in plant health. The roots will be brown and mushy.
• What causes it: Overwatering and poor drainage, common problems with our clay soil and wet summers.
• How to fix/prevent it: Ensure excellent drainage by amending your soil with plenty of organic matter and planting in raised beds if necessary. Water sparingly and avoid overhead watering.
• Shab Disease:
• What it looks like: Brown or black spots on the leaves and stems, often accompanied by wilting and dieback.
• What causes it: A fungal disease that thrives in humid conditions.
• How to fix/prevent it: Improve air circulation by spacing plants adequately. Remove and destroy any infected plant material. Consider using a fungicide as a preventative measure, especially during periods of high humidity.
• Phytophthora:
• What it looks like: Similar to root rot, with yellowing leaves, wilting, and root decay. Can also cause stem lesions.
• What causes it: A soilborne pathogen that flourishes in wet conditions.
• How to fix/prevent it: Improve soil drainage and avoid overwatering. Use disease-free planting material. Fungicides may offer some protection, but prevention is key.

Southeast Specific Challenges: The combination of hot heat, humid humidity, and wet-summer rainfall creates a perfect environment for fungal diseases to attack lavender. Prioritize good drainage, air circulation, and careful watering practices to keep your plants healthy.

Lavender benefits from having companions that thrive in similar conditions. Rosemary, thyme, and sage are excellent choices because they prefer well-drained soil and full sun, just like lavender. They also help deter pests. Roses also make good companions, as they enjoy similar growing conditions and the lavender can help repel aphids.

Avoid planting lavender near mint. Mint is a water hog and can quickly overwhelm lavender, especially in our humid environment, creating conditions that lead to root rot and other problems.