The perennial herbaceous English lavender is best known in Mediterranean regions and has bright, fragrant flowers. Lavender has been used for medicinal, culinary and aromatherapy purposes for years and can easily be grown in the home garden either indoors or outdoors. English lavender will produce flowers for a decade once established, but there are some steps that are important to take when first planting the flowers. Plant lavender indoors in early summer.
Fill the planting container with potting soil. Insert the lavender seeds about 1/4 inch into the soil, spacing them 3 to 4 inches apart. The seeds should barely be covered with soil. Keep the planter in a bright area with indirect sun and water once a week. The seeds should germinate within two to three months.
Transfer the English lavender seedlings once they are a couple inches tall; lightly tug them out of the soil with your fingers and set them in a shallow hole in the new soil. Plant one seedling per 4-inch container. Keep indoors in a bright location through their first winter, and water once per week, letting the soil dry out completely in between watering. Keep them indoors until late spring.
Pick a planting site outside in late spring that receives full sun and has well-drained soil. Make sure there is no chance of frost anymore. Transplant the lavender seedlings outside, keeping them 2 to 3 feet apart.
Water the plants right after planting to let the soil settle, and then water the lavender every two weeks. Lavender does not like wet soil. If you live in a very hot or dry climate, water once per week.
Mulch about three layers around the base of the plants in the late fall season to insulate the lavender roots in cooler weather. Remove any leftover mulch in spring.
Prune back any lavender flowers after the first bloom to promote more growth. Every two years prune back the English lavender plant to 6 inches tall to prevent tangled foliage.