The layering process
Start the layering process in the morning when the hydrangea stem holds the most moisture. Select a flexible low stem at least 1 foot long. A flexible stem indicates new growth and the ability to withstand bending. Pull the stem down to see where the stem will touch the ground closest to the base of the shrub. Note the location where the stem touches the ground and then release the stem.
Make a shallow dip in the soil at the location where the stem touched the soil. Use a hand trowel (or your hand) to scrap away the soil to about 2 inches deep and 6 inches wide.
Harvesting the rooted hydrangea stem
It takes about three months for the buried stem to root. If layering the hydrangea stem in the spring (March or April), harvest the stem before August. If layering the hydrangea stem in the summer, harvest the stem the following spring when new growth appears on the end of the layered stem.
Push a hand trowel beneath the rooted portion of the hydrangea stem. Start the spade 3 to 4 inches from the stem and push down and below the stem about 6 inches. The soil is unlikely to cling to the roots.
Use the hand pruners to snip the stem from the shrub. Make the cut about 3 inches away from the rooting section of the stem. Plant the hydrangea in a pot or the groundHow to care for potted mophead hydrangea
Planting oakleaf hydrangea