Lavender is a common herb originating from the Mediterranean region. Many gardeners envision the purple-flowered plant when they think of lavender, but lavender actually exists in many species and cultivars, some of which develop pink or white flowers. Lavender does survive winter temperatures, with hardiness varying by species.
English lavender remains hardy to U.S. Department of Agriculture plant hardiness zone 5. Other types, such as the French and Spanish lavender plants, do not survive winter temperatures in the northern or middle areas of the United States. In comparison, English lavender performs poorly in many hot Southern climates, such as South Carolina. Lavender grows in the south through zone 9.
Providing ideal growing conditions optimises the health of a plant, allowing it to better survive stressful events such as low temperatures. Providing lavender with full sun and well-drained alkaline soil encourages healthy growth. Placing lavender shrubs in wind protected areas also lessen the effects of low winter temperatures.
Planting lavender in the spring in areas with cold winter temperatures provides the maximum time possible for plants to establish strong, healthy roots to survive the winter. Planting lavender in the fall in zones 5 to 7 should be done only with plants at least 4 inches in height, according to Colorado State University Extension. Watering during the winter when temperatures reach above freezing helps keep plants healthy during this stressful period. Mulching around plants with at least 3 to 4 inches of organic materials also helps protect the roots throughout the winter.
Gardeners in northern climates with winters too severe for lavender to thrive still enjoy lavender by planting it in containers. This requires careful attention to maintain proper moisture and nutrient levels, but allows gardeners to bring the lavender indoors over the winter. Ensure adequate space for lavender in containers, transplanting to larger pots as the plant grows, requiring additional room for its roots.