Lavender is prized for its aromatic foliage and beautiful purple blooms. Successfully cultivating this sun-loving perennial in Georgia presents a significant challenge due to the region’s intense summer heat and persistent high humidity. These conditions are the opposite of the plant’s native dry, rocky Mediterranean habitat, making localized advice on variety selection and soil management necessary for success.
Selecting Lavender Varieties Suited for Georgia’s Climate
Choosing the correct type of lavender is the first step toward overcoming the Southeast’s humid climate. The delicate English lavenders (Lavandula angustifolia), such as ‘Munstead’ or ‘Hidcote,’ struggle significantly with the combination of summer heat and moisture, often leading to rapid decline. Gardeners should instead focus on hybrid varieties specifically bred for improved heat tolerance.
The most reliable choice for Georgia’s USDA Zones 7 and 8 is the Lavandin group (Lavandula x intermedia). Cultivars like ‘Grosso’ and ‘Provence’ offer longer flower spikes, strong fragrance, and the ability to withstand humid summer conditions. The patented ‘Phenomenal’ hybrid is also celebrated for its robust disease resistance and impressive hardiness across temperature extremes.
Spanish lavender (Lavandula stoechas) thrives in hot conditions and offers a distinctive “rabbit ear” bloom structure. Varieties such as ‘Anouk’ or ‘Javelin Forte’ are well-suited to the heat and can tolerate more moisture than the English types. These varieties bloom earlier and for a longer period, providing a greater reward for the effort required to establish them.
Essential Soil Preparation and Drainage
Poor drainage is the single greatest cause of lavender failure in the South, as the plant’s roots are highly susceptible to fungal rot in constantly saturated soil. Georgia’s native heavy clay soil must be aggressively amended to replicate the rocky, lean conditions lavender prefers. The planting site should be modified to ensure water drains away almost instantly, preventing the crown from sitting in moisture.
Start by incorporating large volumes of inert, coarse materials like horticultural sand, fine gravel, or crushed granite grit into the native soil. These materials are far more effective than organic matter at creating the large pore spaces necessary for rapid water percolation. Aim to mix these amendments so that the final soil composition is gritty and extremely fast-draining.
Lavender requires a slightly alkaline soil pH, ideally between 6.5 and 7.5, which is often higher than the naturally acidic soil found in Georgia. Adding dolomitic or calcitic agricultural lime during the soil preparation phase can effectively raise the pH to the optimal range. Building a raised bed or a gentle soil berm at least 12 to 18 inches high helps lift the root crown above the surrounding grade, maximizing drainage and air exposure.
Planting, Watering, and Ongoing Maintenance
When planting, ensure the lavender’s root crown sits slightly above the surrounding soil level in the prepared bed. This technique, known as “planting high,” allows water to shed away from the base of the plant immediately, providing an extra safeguard against crown rot. Space plants according to the mature width of the chosen variety, often 2 to 3 feet apart, which promotes air circulation around the base.
The most common mistake after planting is overwatering, especially once the plant is established. For the first season, water deeply only when the top 2 to 3 inches of soil have completely dried out. Once established, lavender is drought-tolerant; supplemental watering should be reduced and is often unnecessary during the humid summer rain season.
Pruning is important for maintaining plant health, shape, and longevity, as well as encouraging dense, non-woody growth. The primary prune should occur immediately after the first major flush of blooms fades, typically in late summer or early fall. Cut back the spent flower stems and about one-third of the green foliage.
Be careful to avoid cutting into the old, gray, woody base, which does not regenerate new growth. A lighter shaping prune can be done in early spring, removing any dead or damaged winter growth and encouraging the development of new shoots.
Preventing Common Humidity-Related Diseases
The high summer humidity in Georgia creates an ideal environment for various fungal pathogens that attack lavender, even when the soil is perfectly drained. Root and crown rot, caused by soil-borne fungi like Phytophthora species, manifests as sudden wilting and collapse despite moist soil. The preventative drainage measures taken during soil preparation are the best defense against this fatal condition.
Another common issue is Botrytis blight, or gray mold, which flourishes in high humidity and poor airflow. This fungus appears as a fuzzy, gray coating on leaves and stems, often starting at the plant’s base. To prevent this and other leaf spot diseases, water the lavender at the soil level using a drip system or a hose, completely avoiding overhead watering that leaves foliage damp for extended periods.
Ensuring maximum sunlight exposure and maintaining excellent air circulation are important preventative steps. The proper planting spacing allows air currents to move through the foliage, quickly drying any morning dew or rain. Remove any dead leaves or debris from around the plant’s base promptly, as decaying organic matter provides a moist harbor for fungal spores.