How and when to prune hydrangea paniculata

The Hydrangea paniculata or also known as panicle hydrangea is a variety of hydrangeas that comes from Asia and America. It is characterized for being a very strong and resistant variety and for reaching great height, being able to reach 4.50 m. In general, it tends to have a fairly late flowering, which occurs in the form of a panicle or cluster (hence its name). As you can imagine, in this article we will take care of analyzing everything related to pruning Hydrangea paniculata, how and when to do it, with what tools and more.

Although pruning this plant is not a 100% necessary care for its development, it will help us improve the quality of its flowering. If you don’t prune, flowering will still occur, but the size of your flowers will be smaller. It will also spend more energy to develop, reaching greater heights. So if you want a higher quality flowering you should read this post. 😉

1. How to care your Panicle Hydrangea

Although the main topic of the post is the pruning of this floral plant, we do not want to stay only on that. It is useless if you are an expert in pruning this variety of hydrangeas, if you have no idea of its basic care. The plant will end up dying or giving a very poor flowering. Let’s see briefly which are the main ones.

• Location: you like places with semi-shade, especially if the summers are intensely hot. For places with milder summers, you can place it in full sun exposure. In case of severe winters, try to protect it with a thermal blanket.

• Soil: prefers soils with a good amount of organic matter and that also have good drainage capacity.

• Irrigation: it should be watered every 3 or 4 days in times of full development (spring and summer), apply plenty of water but try not to cause floods. When winter arrives, the regularity of the waterings should decrease, it will be enough to water every 7 or 10 days.

• Fertilization: it is good to ensure a better development and a more abundant flowering. Fertilization should begin in the first days of spring and continue until the end of summer with applications every 2 weeks.

• Pests and diseases: they are very resistant plants to problems like these, in general you will not have to worry.

• Pruning: as we have already said, it is very beneficial to improve flowering. In the next sections we will study this point in depth.

2. Tools you need for Pruning Hydrangea paniculata

Although Panicle Hydrangea are garden plants that can grow quite tall, their stems are never very thick. For this reason, the list of tools that we will need to prune is quite small.

In general, we can always prune this variety of hydrangeas simply with manual pruning shears. You may need to cut somewhat tall branches, so a long-handled scissors can also help.

In addition, it will be useful to have a rake and a broom to collect the remains of the pruning, and a pair of gloves to protect your hands during this task.

Returning to the remains of the pruning, and in case your hydrangea has suffered an attack of pests or diseases, try to get rid of these remains in a good way. If you leave them near other plants you can spread this disease or pest throughout your garden.

2.1 How to care for and disinfect your tools

There are two very important tasks regarding pruning tools that many gardeners forget. The first is to give them the necessary maintenance care, and the second is to disinfect them before starting each pruning.

Let’s start by briefly listing the main cares:

• Use the right tool for a job and avoid twisting or straining it.

• Clean and oil tools regularly by wiping an oily cloth on blades and other surfaces.

• Keep cutting edges sharp by regularly using an whetstone.

• Wooden handles should be varnished or regularly treated with linseed oil to keep them from cracking or splintering.

Knowing what the cares are, let’s now see three methods to perform the disinfection correctly:

• Method 1: rub the scissors blades with a cloth dipped in alcohol (ethanol). After cleaning, allow the tool to sit for a couple of minutes for maximum disinfection efficiency.

• Method 2: prepare a mixture 1/9 of chlorine and water (one part of chlorine and 9 of water). Then soak the scissors for half an hour in that mixture. After those 30 minutes you can start pruning.

• Method 3: this third method is effective but from my point of view not so recommended. Here what you should do is pass the blade for a few seconds through a flame. This will disinfect but also burn the blade.

3. Pruning Hydrangea paniculata

Within the Hydrangea paniculata there are many varieties, among the most popular are the Hydrangea paniculata limelight, Hydrangea paniculata pinky winky, PeeGee hydrangeas or grandiflora. Many times it is difficult to distinguish between one variety and another, and generally when it comes to pruning them there are no major differences.

Therefore, in this section we will begin by addressing the topic of pruning hydrangeas paniculata in a general way. Then, in section 5. we will study some more particular details of the different varieties.

3.1 Why to prune

Depending on the plant that we are going to prune, the reasons why we do it vary. It is not the same if it is a fruit tree than if what we have is a floral plant.

In the case of hydrangeas, the reasons why it is necessary to prune them are the following:

• Improves flowering.

• Give a more aesthetic shape to the bush.

• Remove all dead flowers.

• Remove all those branches that are sick, broken or damaged for any reason.

• Cut those branches that are developing crossed or with bad orientation.

There may be other reasons, but the above are by far the most important.

3.2 When to prune

When the question arises of when to prune a Hydrangea paniculata, the question usually arises from not being sure whether it is better to prune in the fall or wait until early spring. The answer to this question is somewhat ambiguous. Although pruning can be done in both seasons, there are pros and cons in each case.

When the question arises of when to prune a Hydrangea paniculata, the question usually arises from not being sure whether it is better to prune in the fall or wait until early spring.

If we talk about pruning during the fall, we have the advantage of preventing the snow from damaging any branch (in the case of very cold areas). During these months in the garden there are fewer tasks to do (we do not water, we fertilize so regularly), this allows us to better organize the pruning work. We also remove all the dried flowers from the plant, which many do not like aesthetically.

On the other hand, if we wait for spring to take out the scissors, we will have the possibility to repair the damage of the snow by cutting those damaged branches. These days the shoots begin to come out, we will have a much clearer image to know where to cut each branch. In addition, as the plant is active, the healing of pruning wounds will be much faster in spring.

It should be added that if the winters where you live are quite mild, with few frosts, it is almost indistinct that you prune in autumn or spring. And now tell me, when do you prefer to prune your Hydrangea paniculata?

3.3 How to prune

To understand well the pruning of Hydrangea paniculata it is important to know how these plants work, especially their flowering. The flowers are generated in new stems, that is, those that are generated in the season. Therefore, pruning will not have negative effects on flowering, quite the opposite. With pruning we will promote the generation of new stronger stems, from which a better flowering will develop.

In the case of a new plant, in the first seasons the pruning should be quite light. Just cut off a few stems, the ones that seem weaker. But let the little plant grow bigger.

With pruning we will promote the generation of new stronger stems, from which a better flowering will develop.

When you have large, strong plants, pruning can be much harder. Hydrangeas respond very well to pruning, so don’t be afraid to cut back a lot of branches. If what you have is a bush-shaped hydrangea, pruning is reduced to cutting all its branches to a third of their size. Also try to find those diseased, damaged or dry branches and cut them at ground level.

Now, if what you have is a Panicle Hydrangea in the shape of a tree, pruning is different. In the first years you should try to shape it, that is, leave a single stem with its main branches. With the shape, pruning is simple, you just have to try to prune regularly so as not to lose this shape. And remember to never cut the central stem and main branches, unless they are in poor condition for some reason.

When you go to cut any branch, always try to do it right above a new shoot. Make the cut diagonally leaving a distance of one centimeter to said bud, as shown in the previous image.

4. Special cases of pruning

We have already studied in a general way how to prune a Panicle Hydrangea, but there are some special cases that escape the generality. Although there are no great secrets, we have determined that it is necessary to do a quick review of each case.

4.1 Hydrangea paniculata limelight

The Hydrangea paniculata ‘Limelight’ is undoubtedly one of the most resistant to cold varieties and with the most vigorous and rapid growth. These characteristics make it one of the hydrangeas most sought after by gardeners. What do we have to know about its pruning?

In general, there are two ways to schedule a pruning of these plants, the first in which we let them grow more freely and the second in which we seek greater size control.

Thus, in the first pruning, all we do is cut the flower stems above a bud. This pruning method will give a large bush in a couple of seasons, which can reach 4 m in height.

The second method is to apply a harder pruning, which due to its vigorous growth is welcome. All stems will be cut in early spring to four buds above ground level. Without forgetting to eliminate all those dry and / or diseased branches.

4.2 Hydrangea paniculata pinky winky

As for the Hydrangea paniculata ‘Pinky Winky’ there is not much difference with the pruning that we have just detailed. Since it blooms in new wood, spring is again a great time to prune.

They also resist strong pruning very well, so to better control their development it is good to cut all the branches at a height of four buds measured from the ground level.

4.3 Hydrangea paniculata grandiflora or PeeGee hydrangeas

The Hydrangea panniculata ‘Grandiflora’ or also known as PeeGee hydrangea is very common to find it formed as a small tree, something that gives them a particular touch compared to other varieties of hydrangeas.

The first thing to do with these plants is to define their shape, and for this we must first be clear about the height we want to give it. In general, a height between 2.50 and 3.5 m is usually given. Taking this into account, you must select the strongest and highest trunk of the plant to be the main stem.

After this cut all the branches to a height of 1 m below the final height you want the tree to have. During a growing season the plant develops approximately 1 m, hence the extent that I recommend cutting back.

In addition, to promote better growth you should cut the branches that come from the main trunk, just above a couple of buds. The following year you will be able to select the strongest branches that come out of the stem to leave them as the main ones, and that will form the structure.

Once the PeeGee hydrangea is tree-shaped, pruning is limited to light maintenance pruning. In them you will cut the branches that arise from the base and you will blunt the twigs at the height of a couple of buds.

5. Pruning Panicle Hydrangea (YouTube Video)

To end this post, which became longer than I had planned, we have selected a very good video tutorial (from the UMDHGIC channel). Look at it, I have no doubt that it will help you review what you have read so far. 😉

More information:

• Hydrangea paniculata– hort.ufl.edu

• Panicle Hydrangea – pwfourstar.com

• The RHS Trial of Hydrangea paniculata – www.rhs.org.uk