Lavender is a woody perennial native to the Mediterranean. The plant enjoys a slightly dry soil and warm sunny conditions. Many varieties will come back year after year even in cold regions. Mulching the plants retains moisture, decreases water needs, insulates the soil and keeps weeds down. Lavender benefits from light mulch in the summer and a heavier application in the winter to protect it from extreme temperatures.
Weed around existing lavender plants in early spring.
Apply mulch around weeded plants or apply it to the bed right after planting new lavender plants in spring. This will prevent weed seed in the soil from sprouting.
Spread 2 to 3 inches of shredded leaves, shredded bark or chunk bark mulch in the bed. Keep it 2 to 3 inches away from the base of the plant. Leave the crown of the plant exposed to air so it can breathe and grow properly. Pebbles or stone mulch works well with lavender, as it provides the best drainage and warms the plant in the summer sun. Lavender can take hot temperatures.
Cut back all remaining flowers in late fall.
Mulch lavender plants for winter protection right before or after the first frost. Avoid mulching when the soil is wet, but wait until it dries out a bit before mulching to prevent root rot. Mound shredded pine bark around the plant or cover it with a few pine boughs to provide adequate protection.
Remove mulch from around plants in spring after all danger of frost is past. The plant will look dead and dried up. It sometimes takes a few weeks of warm temperatures for it to green up and start putting forth shoots.
Keep wood mulch about 1 foot from foundations and wooden walls. This type of mulch can attract termites. Landscape plastic is good to use with lavender, just be sure to keep the crown of the plant exposed for best results.
Never use more than 3 inches of mulch, as it keeps the roots too moist and prevents them from growing. Never use hay to mulch lavender, as it has a tendency to carry weed seeds. Straw is a better mulch and decomposes quickly. You'll probably need to apply it more than once in a season.