3 ways to grow new hydrangeas
Q. My neighbor has a beautiful hydrangea. Can I take a cutting from it and be successful in growing a new plant? How should I do it?
Lorrain from Poland
A. Well, if you are my neighbor – just be sure to ask first.
Propagating plants is a great way to share the beauty of the garden. The most common methods for most shrubs include taking cuttings as Lorrain asks, but also includes dividing and layering. Each method of propagation has its plusses and minuses for both the plants and the gardener.
There are five types of hydrangeas, so knowing the type will determine the best propagation method. You can learn more about hydrangeas with my new factsheet at http://go.osu.edu/hydrangeafacts and download the chart that explains the five types.
Taking cuttings and getting a new plant depends on the species of hydrangea and the time you have to get this done. The cutting could root quickly, or it could take a significant amount of time. It just depends on the plant. Root cuttings are options for some shrubs. There are better times of year to select plant parts for cuttings. Many times, this process can get complicated and take a lot of time. For cuttings, I tend to think it is easier to buy a $30 plant than to take the time to get a new plant from cuttings. Be sure to ask your neighbor the specific cultivar of the plant before heading out to the garden center.
Other methods can be easier.
Most hydrangeas can be propagated by layering. To layer, bend a lower branch to the ground in spring, cover it with soil, then a brick to keep it in place. Leave 6 to 8 inches of the tip out of the soil. This new layer can be removed for transplanting in the late fall or the following spring. Check for rooting, but don’t check it every week. Wait a few months before you check it the first time.
Dividing is another option for some hydrangeas. This can be done during the dormant season before new growth emerges on hydrangeas that form clumps as they grow. Simply dig the roots, then separate the roots and replant. This is the same as dividing hostas or other perennials, but can only be done with certain types of hydrangeas. I find that smooth hydrangeas (Hydrangea arborescens) can be treated like a perennial and is easily divided. The center of some of these gets old after five to six years and the plant can benefit from being divided. How often you divide these depends on the size of the clump and how quickly the plant grows.
Eric Barrett is OSU Extension educator for agriculture and natural resources in Mahoning County. Call the office plant and pest clinic at 330-533-5538 to submit your questions. Regular clinic hours are 9 a.m. to noon Mondays and Thursdays.