Of all the propagation methods out there, I find that this one works every time. So even though it takes a long time, it is worth the wait. Typically, I layer many branches in the spring or fall, then forget about them for a few months. Then, with great joy, I cut the branch off the parent plant, dig up the new plant and move it to its new place.
Pros
• There is no stress on the host plant.
• This is a low maintenance way of propagating plants.
• It works every time, 100%.
Cons
• It takes a long time for roots to form.
• Potentially low productivity (if compared to taking cuttings from a plant)
How to
1. Parent plant; feeds the layered branch while adventitious roots are initiated
2. Layered branch with adventitious roots forming
3. Weight keeping the layered branch in place
4. Where to cut once the branch has rooted
2. Layered branch with adventitious roots forming
3. Weight keeping the layered branch in place
4. Where to cut once the branch has rooted
Select a branch: On a shrub, select branches near the ground, or branches that bend down to the ground easily.
Strip the middle section of leaves; You can scar that section too, to promote root growth. Rooting hormone can also be applied at this step.
Bend the branch down and eyeball where to dig a hole: Dig a 2 – 3 inch deep and 6 – 12 inch long hole into which you bend the middle section of the branch.
Cover it up and secure it: While holding the branch in place, backfill the hole with soil, then place a rock on top of it.
Alternatives
Securing the branch: I use rocks or brick. Pros use small stakes in the ground (think tent pins pinning the branch down in the hole before backfilling it with soil).
New roots are forming on the stripped branch underground, while the branch is still attached to and nourished by the host plant.
Other types of layering
Simple layering is my favorite, but there are other types too, suitable for various types of plants:
Tip layering: When you bed the tip of branch down into contact with the soil, and roots form at the end. Blackberry shrubs does this naturally; they are ‘walking’ away, as some would say.
Trench layering: Used for plants with strong apical dominance (center stem grows stronger than side stems). Bury a whole stem and let only the tip peek out at the end. Each node should produce a new shoot.
Serpentine layering: Used for very flexible branches. Weave it in and out of the soil, pinning each ‘dip’ down with a pin or a rock. many smaller plants will be produced.
Mound layering: Often used for heavy-stemmed shrubs and trees. Clip the stems down to about 2 ft off the ground. Strip the leaves of the lower portion of remaining branches. Cover with soil shaped like a mound, leaving the leaved tips peeking out at the top.
Air layering: Often used for heavy-stemmed shrubs and trees. Peel the bark off a 2 inch section, exposing the green cambium layer. Cover with moss and / or soil, then with dark plastic to keep light out. Make sure it is fastened securely. Movement will inhibit root development.
A simple rock hold the branch firmly in place so that roots can form undisturbed.