Lavender, prized for its aromatic uses, often faces suspicion from gardeners in colder climates. Whether this semi-woody perennial dies in the winter is conditional. Lavender generally survives, but its survival through freezing temperatures depends entirely on the specific variety planted and the winter protection it receives. The greatest threat is often not the cold air itself, but cold, wet soil that causes root rot.
Survival Based on Lavender Variety
Lavender’s capacity to endure winter is linked to its genetic makeup, specifically its species and cultivar. Gardeners improve success by understanding the cold hardiness associated with different types, measured by the USDA Hardiness Zones.
English Lavender (Lavandula angustifolia) is the most resilient species, reliably surviving in USDA Zones 5 through 8, and often into Zone 4 with adequate protection. Cultivars like ‘Munstead’ and ‘Hidcote’ are celebrated for their superior hardiness, able to withstand temperatures well below freezing because they fully enter a protective dormancy state. This species is the perennial choice for northern gardeners, requiring minimal preparation to ensure its woody base survives.
In contrast, varieties such as French Lavender (Lavandula dentata), Spanish Lavender (L. stoechas), and many Lavandin hybrids (L. x intermedia) are considered tender. These varieties are generally only reliably hardy in Zones 7 or 8 and warmer. In regions with harsh winters, these plants lack the necessary cold tolerance and will likely suffer severe dieback or complete death if left exposed. For these less-hardy varieties, winter survival requires growing them in containers and moving them to a protected environment.
Understanding Winter Dormancy
Lavender’s ability to survive winter hinges on dormancy, a protective resting phase common in perennial plants. This process is naturally triggered by decreasing temperatures and the shortening daylight hours of late autumn.
During dormancy, the plant dramatically slows its metabolic activity, stopping visible growth and conserving energy within its root system and woody crown. The foliage often turns brown, gray, or twiggy, which leads many gardeners to mistakenly believe the plant has died. This outward appearance of decline is actually a sign that the plant is correctly preparing to withstand the cold.
The plant focuses on survival, relying on stored energy rather than new growth, which would be susceptible to frost damage. Do not assume the plant is lost until new green shoots fail to appear from the woody base in the spring, well after the last hard frost.
Essential Winter Preparation
Even the hardiest lavender varieties benefit from preparation that maximizes their chances of surviving the winter. Proper preparation focuses on managing moisture and providing insulation without suffocating the plant.
Pruning should be completed in late summer or early fall, immediately after the main bloom, to remove spent flower stalks and shape the plant. Avoid heavy pruning late in the season, as this stimulates tender new growth susceptible to freezing. Pruning should only remove about one-third of the green growth, leaving the woody structure intact.
The greatest winter killer for lavender is cold, wet soil, which leads to root rot. Ensuring the plant is in fast-draining, gravelly soil is the most important defense. A light, coarse mulch, such as straw or pine needles, can be applied around the base to insulate the roots from sharp temperature fluctuations. Crucially, this mulch must be kept a few inches away from the plant’s crown to ensure air circulation and prevent moisture from collecting against the stem.
For container-grown lavender, especially the tender French or Spanish types, winter survival requires moving the plant to a sheltered location. An unheated garage, cool basement, or shed provides a protected space where the temperature remains consistently cool but above freezing. Watering should be significantly reduced during this period, giving the plant only enough moisture to prevent the roots from completely drying out.