Lavender in Zone 7A — Midwest

Lavender is worth growing in the Midwest for its fragrance and versatility. The scent is lovely in the garden, and the flowers can be dried for crafts, used in cooking, or even brewed into a relaxing tea. Plus, that silvery foliage looks fantastic against our fertile Midwest soil.

Our Midwest weather can be a bit unpredictable, with cold winters and occasional summer heat spells. But with a little planning and attention to timing, you can absolutely grow beautiful lavender here. Our 193-day growing season gives lavender plenty of time to mature and bloom.

Starting lavender from seed indoors is possible, but honestly, it can be a bit tricky. Lavender seeds are slow to germinate, and the seedlings are delicate. If you're up for a challenge, you can start seeds indoors from early to late February, about 10 weeks before transplanting.

Use seed trays with a well-draining seed starting mix. Keep the soil consistently moist (bottom watering helps prevent damping off) and provide plenty of light, either from a sunny window or a grow light. Remember, our springs here in the Midwest can be moderate-to-late, so be patient and don't rush to transplant too early.

For reliable results, I usually recommend buying lavender starts from a local nursery. Transplant them outdoors from late April through mid May. Before planting, harden off your seedlings by gradually exposing them to outdoor conditions for about a week.

When transplanting, space your lavender plants 12-18 inches apart in a sunny spot with well-drained soil. Keep an eye on the weather forecast, as we can sometimes get a late frost in early spring.

Lavender is very drought-tolerant and thrives in poor, dry soil, so be careful not to overwater it, especially with our wet-summer rainfall. Overwatering and humidity are the main enemies of lavender here in the Midwest. Excellent drainage is a must.

During the spring, when we're getting regular rainfall, you probably won't need to water your lavender much at all. Once summer heat spells arrive, check the soil moisture regularly. Stick your finger about 2 inches deep into the soil. If it feels dry, it's time to water. Aim for about 1 inch of water per week, watering at the base of the plant to avoid wetting the foliage and encouraging fungal diseases in our moderate-to-humid climate.

Yellowing leaves can be a sign of overwatering, while wilting leaves indicate underwatering. A light mulch of gravel or pebbles can help improve drainage and prevent the soil from staying too wet, which is especially helpful with our clay soil.

Pruning is important for keeping your lavender plants healthy and productive. After flowering, deadhead the spent blooms and prune the plant into a nice, rounded mound. Cut back by about 1/3, but be careful never to cut into old wood, as it won't regrow.

Prune your lavender plants in late summer, after the first flush of blooms. This will encourage a second, smaller bloom in the fall. As first frost approaches around mid- October, stop pruning to allow the plant to harden off for winter.

You can expect your first lavender harvest from late July through early September. The best time to harvest is when the flower buds are colored but not fully open. This is when the fragrance is most intense.

To harvest, cut the long stems in the morning, after the dew has dried. Gather the stems into small bundles and dry them upside down in a cool, dark, well-ventilated place. Regular harvesting encourages continued production throughout the summer. As first frost approaches (mid- October), harvest any remaining flowers to dry for winter use.

Here are three common problems you might encounter growing lavender in the Midwest:

Root Rot from Overwatering *What it looks like:* Yellowing leaves, wilting, and a general decline in plant health. The roots may be brown and mushy. *What causes it:* Overwatering, especially in our wet-summer climate, and poorly draining soil. Clay soil exacerbates the problem. *How to fix/prevent it:* Ensure excellent drainage by amending your soil with sand or gravel. Water only when the soil is dry to the touch. Avoid overwatering, especially during rainy periods.

Shab Disease *What it looks like:* Brown or black spots on the leaves and stems, often starting at the base of the plant. *What causes it:* A fungal disease that thrives in humid conditions. *How to fix/prevent it:* Improve air circulation around the plant by spacing plants adequately and pruning to open up the center. Remove and destroy any infected plant material. Fungicides may be necessary in severe cases.

Phytophthora *What it looks like:* Rapid wilting and death of the plant. The roots may be discolored and decayed. *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. There is no cure once a plant is infected.

Midwest Specific Challenges: Our moderate-to-hot summer heat, moderate-to-humid humidity, and wet-summer rainfall can create a challenging environment for lavender. Be sure to provide excellent drainage, avoid overwatering, and monitor your plants regularly for signs of disease.

Lavender makes a great companion plant for rosemary, thyme, and sage. These herbs all prefer similar growing conditions – full sun and well-drained soil – and their aromatic foliage can help deter pests. Roses also benefit from being planted near lavender, as the lavender can help to repel aphids.

Avoid planting lavender near mint. Mint is a vigorous grower that can quickly spread and crowd out lavender. Mint also prefers moist soil, which is the opposite of what lavender needs.