That's why I prefer to do most of my planting of small plants in the spring. Since the invention of intermittent misting equipment, not very many commercial nurseries use layering as a means of propagation. It is too labor intensive for the number of new layers a nursery can obtain. It also ties up valuable field space that could be used for more productive things. Keep in mind that wholesale nurseries produce plants by the tens of thousands.
Nurseries have to keep a whole block of 'stock' plants that are to be used for nothing but layering.
A good stock plant might yield 30 or 40 layers, where the same 'stock' plant could yield several hundred softwood cuttings. Understanding how the commercial nurserymen do layering will help you achieve better results at home. This new growth is the ideal wood for layering. If you prune the shrub heavily the year before you intend to use it for layering, it will produce a substantial amount of new growth that will be ideal for the layering process. I would actually cut the shrub to within six or seven inches from the ground.