Hydrangeas are spectacular deciduous flowering shrubs that are usually sold as well-developed plants in 1-gallon or 2-gallon pots at a premium price—$25 to $50 is not an uncommon price for nursery hydrangeas. Thus, there's an incentive to save money by propagating your own hydrangeas by taking stem cuttings and rooting them. A mature plant can yield dozens of new hydrangeas to fill your garden, potentially saving you hundreds of dollars.
Hydrangeas are especially well-suited to this method. Unlike many other woody plants, they grow quickly and can become mature flowering shrubs within a single year.
It is technically a violation of the law to propagate plant varieties that have been patented by their developers. Plant patents remain in effect for 20 years after they are first granted, so older varieties of plants can generally be propagated without a problem. But a plant whose nursery tag includes a "TM" or "®" is probably patented and should not be propagated without permission. Plant patent law is rarely enforced against private homeowners who are merely cloning plants they already own, but there is still the potential for legal difficulties if you are caught violating a plant patent.
When to Grow Hydrangeas from Cuttings
Theories abound regarding the best time to take cuttings from the various types of hydrangea (big-leaf, oak-leaf, smooth, and panicle), but most experienced gardeners find it best to take cuttings in spring in order to grow them into viable plants for planting in the garden a few months later, in the fall. In spring, the plant's metabolism and growth rate are peaking, and spring propagation allows for a full growing season for rooted cutting to mature into a full-sized plant.
It's best to take cuttings during the cool of the day, in the early morning or evening. This way, heat stress won't affect the vulnerable stem once it's been removed from the parent plant.
While it is possible to take hydrangea cutting in late summer or fall to root and grow indoors, most growers find this to be a trickier method with a lower success rate.
Before Getting Started
There are several popular species of hydrangea, each with slightly different needs and growing characteristics:
- Hydrangea macrophylla (big leaf hydrangea): Growing 6 to 10 feet tall with flowers in blue to pink to white, this species is hardy in USDA zones 5 to 11. Some growers believe that early fall is the best time to take cuttings from this type, which seems to be more accepting of indoor growing, but spring cuttings also seem to work fine.
- Hydrangea arborescens (smooth hydrangea): Growing 3 to 5 feet tall with white flowers, this species is hardy in zones 3 to 9. This type is often propagated by root cuttings, though stem cuttings can also work.
- Hydrangea quercifolia (oakleaf hydrangea): Growing to about 8 feet tall with white blooms, this species is hardy in zones 5 to 9. Take cuttings from non-blooming stems in early spring, then root it in a pot until a good network of roots has developed.
- Hydrangea paniculata (tree hydrangea, panicle hydrangea): Growing 8 to 15 feet tall with white to pink flowers, this variety is hardy in zones 3 to 8. These, too, are best rooted in spring to produce new garden plants for the fall.
It's worth reading up on the various types of hydrangea to make sure you understand the needs of the new plants you are creating. Be aware that each species has many different cultivars, each with its own unique characteristics.
Learn How to Grow Hydrangeas From Cuttings
Equipment / Tools
- Sharp pruners
- Gardening gloves
- Rubbing alcohol
- Cotton ball
- Powdered rooting hormone
- 8- to 10-inch terra cotta pot
- Sterile seed-starting soil
Sanitize Your Pruners
Sanitize your pruners by dabbing a cotton ball into rubbing alcohol and wiping down the blades and handle. Taking this precaution will help to prevent fungal diseases in your new plant.
On a mature hydrangea plant, make a cut about 2 inches below a leaf node on a green, healthy branch that has not yet formed flower buds. Avoid older, woody stems. The cutting should be 6 to 8 inches long, overall.
Trim the Leaves
Remove all but the top two to four highest leaves on the cutting with your pruners, being careful not to damage the stem in the process. When cutting the leaves, leaving some room between the main stem and the cut. This allows the integrity of the main stem to remain undamaged.
Remove half of each of the remaining upper leaves, using pruners or scissors.
Dip Stem into Rooting Powder
Dip the cut end of the stem into rooting hormone powder. This can be viewed as an optional step, but most growers find that success rates are improved by using rooting hormone.
Prepare a Pot
Choose a pot that meets your space needs and the number of hydrangea cuttings you are starting. An 8- to 10-inch terra-cotta pot should hold several cuttings.
Add a seed-starting potting mix to your pot, then moisten the mix thoroughly. Other sterile growing media can also work, such as vermiculite or coarse sand.
Plant the Cuttings
Embed each cutting into the growing mix all the way up to the base of the remaining leaves. Pack the mix down around stems and moisten thoroughly.
Place the potted cuttings in a loosely secured clear plastic bag and set it in a location that gets bright indirect light, but not direct sunlight, which can bake the cuttings and cause them to rot.
Monitor the potting mix and add moisture when it begins to dry out to the touch. The growing mix should be consistently moist, but not soggy.
Repot as Needed
Within a month, your hydrangea cuttings will form new roots. Once they do and new green growth begins, you can carefully transplant individual cuttings into their own pots filled with ordinary potting mix to continue growing into larger plants. Or, well-developed cuttings can be transplanted directly into the garden at this time.
You can now begin treating the new specimens as mature plants, watering them weekly.
Transplant into the Garden
When planting new hydrangeas into the garden, follow proper spacing guidelines for by allowing a 4- to 6-foot gap between plants. If planted in the fall, the new hydrangeas will grow into flowering bushes during the next growing season.