Propagating lavender can also be done by mound layering. This type of layering works well with woody base shrubby upright herbs like lavender.
In early spring prune the branches off of the lavender plant so the plant is only about 2 to 3 inches above the ground.
Check your plant weekly, and in one or two weeks it should be sending out new shoots.
When the new shoots are about 5 inches high, you mound it. Equal amounts of sand and peat moss work well. Cover the plant until only the tops of the plant is peeking out of the soil. Keep this mound slightly moist.
As the shoots continue to grow, add more soil until the mound is about 8 inches high. Always leave the tops out so it can get sunlight.
Have a bed prepared for your new plants.
In late summer on a cloudy day, wash away the mounded soil or gently dig it out.
Using a sharp pruner, cut each rooted stem off of the mother plant. Plant the rooted stems right away.
The mother plant will grow back into a nice healthy plant or you can use this plant for lavender babies next year.
Then sit back and enjoy your beautiful lavender garden!