Climbing hydrangeas can be propagated by taking cuttings in the spring or early summer, or by layering in early summer.
Cuttings
- In the spring, look for young, non-flowering shoots with three sets of leaves.
- Cut a 3–5 inch section of the stem just below a leaf node.
- Remove all but the top two leaves.
- Dip the cut end in rooting hormone.
- Insert the cutting into a pot of damp potting mix.
- Cover the pot with a plastic bag or dome.
- Keep the cutting moist and in a warm spot with indirect light.
- After about a month, the cutting should have roots.
- Transplant the cutting into an individual pot.
Layering
- Find a shoot that’s close to the ground.
- Lower the shoot into the soil and secure it.
- Roots will form along the shoot.
- The mother plant will need to provide water and nutrients to the offshoot during the transition phase.
You can also propagate climbing hydrangeas by dividing them in the spring or fall when the plant is dormant.