Hydrangeas are so easy to propagate that I rarely buy new ones, unless I want a variety that I don’t already have. And even then, I first ask around to see if any of my friends can spot me some cuttings.
Little effort goes into propagating a hydrangea plant, as I’ll show you in this step-by-step guide.
Hydrangea Propagation with Cuttings
The easiest way to propagate hydrangeas is through cuttings. But you do need to pay attention to how to harvest the cuttings and care for them until they get established.
As for the steps involved, here’s a quick rundown of the process:
Step 1: Harvesting the cuttings
Harvest healthy, pest and disease-free cuttings, preferably ones without bloom buds. You want your cuttings to be focused on rooting, not diverting energy to blooms.
Choose vibrant green cuttings that are around 3 to 5 inches long and have at least 3 leaf nodes. Use sharp and clean pruning shears to cut the stem above a leaf node.
Step 2: Place the cuttings in moist potting medium
Use a soil-less potting medium like those that contain peat moss and perlite to root the cuttings. Alternatively, you can use seed starter medium. Bury at least one, but preferably two of the three leaf nodes in the potting mix.
Optionally, you can coat the stems in a bit of rooting hormone to speed up the rooting process, but if you’re not in a hurry, you can skip the rooting hormone. Your hydrangeas will root regardless.
I often get asked about the pot I use for rooting. For rooting, I use 8 to 10 inch pots.
I sometimes use plastic pots, other times I use terracotta pots. At this stage, you can use whichever, I found no benefit or drawback of using one over the other.
If you plan on growing hydrangeas in pots, a terracotta one would be better when the plant has grown rather large to prevent it from tipping over.
Step 3: Keep the cuttings in a bright location, out of direct sunlight
Maintain good soil moisture and keep the cuttings in a warm location. They need bright, indirect sunlight. Direct sunlight can burn the delicate leaves, but also cause the potting medium to dry out more quickly.
You must also be careful not to overwater your hydrangeas. Excess water that will not drain will only cause rotting.
In about 4-6 weeks the roots of your newly rooted hydrangea should be strong enough that you can move the plant to a larger pot or you can plant it in the garden.
When Should You to Propagate Hydrangea?
I propagate hydrangeas in spring. This is when the plant’s metabolism is at its peak. Propagating in spring also allows the plant an entire season to mature, making it easier for it to survive the winter.
Plus, by propagating in spring, you can have your hydrangea blooming in the next season.
Can You Root Hydrangea Cuttings in Water?
I must admit that I have always used moist potting medium to root hydrangeas. But as far as I know, they should root just as well in water.
Friends who’ve tried rooting hydrangeas in water tell me that despite their hydrangeas growing roots, these roots are not strong enough to survive transplantation into soil, and cuttings soon die after being transplanted.
Now, I don’t know if they should have waited more for the roots to grow stronger in water, or that they failed to give the transplanted cutting proper after care, or that they’re right and hydrangeas just simply don’t grow as strong a root system as they do in soil.
So, from what I gather, rooting hydrangeas in moist potting medium has a higher success rate than rooting them in water. Since I haven’t tried it myself, I cannot say for certain that this is true.
My only problem with the water rooting method is that you need to remember to replace the water frequently and clean the glass container each time, something that I’m prone to forgetting.
So, if the water rooting method is something you find easier or you want to test to see how it works out for you, you simply need to follow the same steps I recommended for rooting in potting medium. Except you use water instead of soil.
And make sure to trim the bottom leaves off the cutting, so that only the stem of the cutting sits in water!
How Long Does it Take Hydrangea Cuttings to Root?
From my experience, roots will usually form within a month from planting the cutting. This timeframe can vary based on the environmental conditions (warmth, moisture, light, etc.) and whether you use rooting hormone or not.
In the first two weeks of planting the cuttings, you need to pay close attention to keeping the potting medium moist. After two weeks, you can cut back a bit on watering and start watering the hydrangea as you normally would.
Now, just because the roots have started to form within the one month timeframe, it doesn’t mean you can already transplant the cutting. I’d wait a few more weeks to make sure those roots are really strong and well-established.
If you’re rooting in water, you should expect about the same timeframe to play out as well. As I mentioned, wait a bit longer for the roots to really get strong enough before you move the plantlet to a new pot or in your garden.
Failure of cuttings to get established because of a delicate root system is something you can avoid simply by postponing to move your hydrangea plantlets for a couple of weeks.
Propagating hydrangeas from stem cuttings can be achieved in 3 easy steps. Once you know how to harvest the stems and how to take care of the cutting to stimulate rooting, there’s really no reason to buy new hydrangeas, unless you want a variety you can’t get from friends or acquaintances.
Keep the planted cuttings in a warm location, make sure they’re not exposed to direct light. They should receive bright indirect light. Keep the soil moist but not wet, and you should see some plant activity in about a month or so.