Lavender in Zone 6A — Great Plains

Lavender is a fantastic addition to any Great Plains garden. Its fragrance is wonderful, it attracts pollinators, and it’s versatile for crafts and cooking. Plus, it's beautiful! Lavender thrives in our intense sunshine and relatively low humidity, making it a good fit for our region.

Growing Lavender in the Plains has its challenges, of course. Our extreme weather and variable rainfall can be tricky. But with the right timing and care, you can absolutely enjoy this fragrant herb within our roughly 188-day growing season.

Starting Lavender from seed indoors is possible, but it can be slow and sometimes frustrating. If you're up for the challenge, begin in mid February through early March, about ten weeks before you plan to transplant. You'll need seed trays, a warm location (a heat mat helps), and grow lights to provide consistent light.

Remember to water from the bottom to prevent damping off. Our spring weather can be so variable, so having a backup plan of buying starts from a local nursery is always a good idea!

Transplant your Lavender outdoors in late April through mid May, once the danger of hard frost has passed. Before transplanting, harden off your seedlings by gradually exposing them to outdoor conditions for about a week. This helps them adjust to our sometimes harsh Plains winds and temperature swings.

Space your plants 12-18 inches apart in a sunny spot with well-draining soil. Honestly, buying established plants from a local nursery is often the most reliable way to get a good start with Lavender here.

Lavender is very drought-tolerant, which is a huge plus in our Great Plains climate. Overwatering is far more of a threat than underwatering. The key is to provide excellent drainage and avoid excessive moisture, especially during our more humid stretches.

During the growing season, water deeply but infrequently. A good rule of thumb is to check the soil about two inches down. If it's dry, it's time to water. Generally, about 1 inch of water per week is sufficient, but adjust based on rainfall. Water at the base of the plant rather than overhead to minimize humidity around the foliage.

Yellowing leaves can indicate overwatering, while wilting can signal underwatering. A light mulch of gravel or rock around the base of the plant can help improve drainage and retain some moisture without suffocating the roots.

Pruning is essential for maintaining a healthy and productive Lavender plant. After the flowers fade, usually in late summer, deadhead the spent blooms. This encourages new growth and prevents the plant from becoming leggy.

Shape the plant into a mound by cutting back about one-third of the growth. Be careful not to cut into the old wood, as Lavender doesn't typically regrow from there. As the first frost approaches around mid- October, stop pruning to allow the plant to harden off for winter.

You can expect your first Lavender harvest in late July through early September, depending on the variety and the growing season. The best time to harvest is when the flower buds are showing color but haven't fully opened. This is when the fragrance is most intense.

Cut the stems long in the morning after the dew has dried. Gather them into small bundles and hang them upside down in a cool, dry, dark place to dry. Harvesting regularly encourages continuous flowering, so keep an eye on your plants and snip those stems! As the first frost nears, harvest any remaining buds to dry indoors.

Here are three common problems you might encounter growing Lavender in the Great Plains:

Root Rot from Overwatering

• What it looks like: Yellowing leaves, wilting, and a general decline in plant health. The roots may appear brown and mushy.
• What causes it: Poor drainage and excessive watering, especially during periods of heavy rainfall. Our variable rainfall can make this tricky.
• How to fix/prevent it: Ensure excellent drainage by planting in well-draining soil. Water sparingly, allowing the soil to dry out between waterings. Consider raised beds or amending heavy clay soils.

Shab Disease

• What it looks like: Grayish-brown spots on the leaves and stems, often accompanied by a foul odor.
• What causes it: A fungal infection favored by humid conditions. Though we have low-to-moderate humidity overall, this can still be a problem in certain microclimates or during wetter years.
• How to fix/prevent it: Improve air circulation by spacing plants adequately and pruning regularly. Remove and destroy infected plant parts. Fungicides may be necessary in severe cases.

Phytophthora

• What it looks like: Sudden wilting and death of the plant, often accompanied by dark lesions on the stems near the soil line.
• What causes it: A soilborne pathogen that thrives in wet conditions.
• How to fix/prevent it: Ensure excellent drainage. Avoid overwatering. Use disease-free plants. Solarize the soil before planting.

Great Plains Specific Challenges: Our hot summer heat, low-to-moderate humidity, and variable rainfall create a unique set of challenges for Lavender. While Lavender loves the sun, extreme heat can stress the plant. Focus on proper watering techniques to avoid both drought stress and root rot.

Lavender thrives alongside plants that share its love for sunshine and well-drained soil. Rosemary, thyme, and sage make excellent companions because they enjoy similar growing conditions and can even help deter pests. Roses also benefit from being planted near Lavender, as Lavender can help repel aphids.

Avoid planting Lavender near mint. Mint is aggressive and can quickly overtake Lavender, competing for resources and potentially creating overly moist conditions that Lavender dislikes.