When you are an owner of a nursery you tend to pick up a bit of information here and then and when combined with nearly 4 decades of this type of growing it does add up over time.
If you want or need more information about serpentine (compound) layering just Google it and you will find a good deal of info.
Then there was the small bit about it above to begin with.
Compound (serpentine) layering is similar to simple layering, but several layers can result from a single stem. Bend the stem to the rooting medium as for simple layering, but alternately cover and expose sections of the stem. Each section should have at least one bud exposed and one bud covered with soil. Wound the lower side of each stem section to be covered (Figure 3). This method works well for plants producing vine-like growth such as heart-leaf philodendron, pothos, wisteria, clematis, and grapes.
Figure 3.
