Hydrangeas are shrubs that are available in many varieties, including ones that can grow as tall as 25 feet; however, most hydrangeas grow about 4 feet wide and 4 feet tall. One way to propagate hydrangeas is from cuttings. While many gardeners simply take a cutting and plant it in a shady area, you may be more successful rooting the cutting prior to freeing it from the parent bush. Start this process in late spring or summer (April to August).
Remove the mulch and other debris on any side of your plant. Bend down a healthy low branch so that it touches the soil. Secure the branch at the point that it touches the soil with a brick or large rock.
Wait two weeks and lift up the brick. Check to see if the branch has rooted by gently tugging on it. If it has not rooted, wait another week.
Amend the soil of the new planting site. In a shady area, till an area that is about 3 by 3 feet and 18 inches deep. Add several inches of compost to help with drainage.
Cut the branch free from the existing hydrangea and gently dig up the newly rooted cutting, being sure to get all of its roots.
Plant the cutting in the center of the new planting site. Water it, and then tamp down the soil so it is firm and there are no air pockets. Continue to keep the soil moist until the end of fall.