Lavender is an aromatic herb easily propagated by a variety of methods. Seeds, cuttings, layering and division can all be used. The greatest difficulty you'll face when growing this versatile garden essential is which wonderful variety to plant first.
Full sun and dry conditions will give you the best results with lavender. Lavender can be grown as a container plant indoors. This is not ideal, however. Limited light will produce an inferior plant. Soil that is too rich will tend to make herbs that are leafy, but less aromatic. A moderately rich, well drained, slightly alkaline sandy soil is ideal. Allow space for the plant to grow with good circulation. Lavender does not like to be crowded.
Sow the seeds directly in the garden in early spring. Lavender seeds are quite small. Take care when planting that they neither blow away nor are buried too deeply. Barely cover them with soil, and tamp gently. Sprinkle the seeds with water. Keep them evenly moist until germination.
Seeds can be germinated inside as well. By planting indoors, growers give seeds extra time for germination while conditions outside are too cold. Use flats or other shallow containers filled with a sterile growing medium or potting soil. Plant the seed as you would outdoors, and water lightly. A sunny southern or western window will provide the necessary light. Once the plants are large enough to handle safely, they can be transplanted into the garden. Acclimatize the young plants to the growing conditions of their new home before transplanting. This will minimize shock to the plant allowing it to flourish.
Cuttings allow a gardener greater confidence about the quality of the growing plants than is possible with seed. Seed will not always grow true to its parent. A cutting is genetically identical, and will match its parent in every characteristic. Tip cuttings root most easily. Cut a 2- to 6-inch piece of green growth from the plant with a sharp knife or cutter. Remove the leaves, leaving only the uppermost pair. Nick or abrade the stem before applying rooting hormone at the base. Place the cutting in moistened growing media or potting soil in a small container. Keep the pot in a warm, modestly sunny location. Apply bottom heat if possible to stimulate growth. Roots will develop in about 2 weeks.
This is perhaps the most reliable method of lavender propagation available. Roots are grown on a stem that is still supported by the parent plant. This allows a robust young plant to be grown in very little time. Simply bend a green stem to the ground level and pin it in place. Nick the stem lightly at the ground level before applying rooting hormone. Cover the stem with soil leaving the tip exposed. In about two weeks roots will have grown where the stem is buried. When they have grown sufficiently to support it, the new plant can be severed from its parent. Depending on the local growing conditions and time of year, the young plant can be left in place for a season, or transplanted immediately.
Mature lavender plants can be dug up while dormant. The plant is cut or pulled into several sections, each having an adequate amount of root to support the stems. Cut away heavy, woody or dead portions. Replant the healthy sections in the garden or in containers and water lightly. Once reestablished, the plants will thrive anew.