Lavender is a famous Mediterranean plant. Propagating lavender is possible through seed, cuttings, layering (ground and air). In some cases, division of the lavender clump is also an option.
- Read also: growing lavender
Seeds, easy but slow and not always true to form
Natural lavender varieties have succeeded in reproducing through seeds over millennia. However, due to cross-pollination, the children plants are never 100% identical to the mother plant.
Lavender seeds are tiny, between 1 and 2 millimeters long. Germination, even in ideal settings, isn’t guaranteed. Sometimes a seed will sprout within a week, sometimes it might need 3 months! Here, the picture shows commercial seeds. These have a protective coating on them that help retain moisture and make germination more certain. In the main lavender article, you can find a picture of lavender seeds without any coating.
- Starting lavender off from seed is a very slow process. Not only regarding germination: even the seedlings start out very slow! It will take two years before the first flowers appear.
- Expect good surprises: today’s most sold-ever variety, Lavandin, is a natural hybrid between two different lavender species!
Note that some lavender varieties are sterile. They either won’t make seeds, or seeds will appear but never germinate.
Cuttings, the way to go for large quantities
In summer, new branches can be snipped off from your favorite lavender shrub. Plants prepared from cuttings will already bear at least one or two flowers in the following year.
Lavender cuttings are prepared from recent wood. Ideally, growth that appeared since spring has started is best. There must still be leaves on the wood. If not, it’s too old.
- Cut sections that are around 5-6 inches long (12-15cm)
- Follow these instructions: using stems to make cuttings
Layering, a solution to replenish lines of lavender
Layering is the art of bending a branch down to the soil. There, it’s partly buried under soil, with a leafy portion of the branch sticking out on the other side. Roots form on the underground portion. After a season, sometimes two, the branch can be cut free from the mother plant.
With careful transplanting, it can be set up in a new growing spot. When you’re filling in a spot along a line, though, you can simply layer branches from two neighboring plants and leave them in place.
- More on layering lavender
Crown division, splitting the clump
Larger lavender plants tend to layer spontaneously. In some cases, seeds might have self-sown and grown under the mother plant. You can divide the shrub in all these cases where your lavender bush has several live stems or trunks.
- Note: you cannot divide a lavender shrub that has only one stem. Trying to do so will kill the plant.
To separate the different plants that form a lavender that’s grown too large, follow these steps:
- Make sure each stem you’re looking at has both leafage and a root system.
- Half-way between two plants, plunge a sharp spade into the ground along a line. This is to cut any roots that might be connecting the two lavender plants.
- With the spade or a spading fork, lift one of the lavender plants out of the ground with its entire root ball.
- Transplant this to its new grow spot (plant it there as you would normally plant lavender).
Air-layering, great to get potted lavender
A variation of layering is to “bring the soil up instead of twisting the branch down”. This technique is called air-layering, but it also goes by the name marcotting or marcottage.
- How to air-layer lavender
A small pouch with soil is wrapped around a portion of the lavender stem. This stem, young and still bearing green leaves, will grow roots in the pouch of soil. After a few months at most, rootlets colonize the handful of soil they were given. It’s ready to be cut off from the mother branch (under the pouch, not above it!).
This solution is perfect for potted lavender, since it creates a short seedling with a root clump that will bear flowers already in the next season.