Hydrangeas are a wide variety of flowering plants generally known for their clumps of brightly colored flowers forming a globe. They are usually easy to grow, but you need to know what variety you have to provide its pruning or cutting needs.
Cutting your hydrangeas to the ground will give them enough energy to bounce back with new healthy shoots by spring and beautiful blooms by summer. However, this is ideal only for hydrangea varieties that bloom on new wood.
In this article, you will find out if it’s necessary to cut your hydrangeas to the ground and how to correctly prune popular varieties of hydrangea. Read on!
Do You Have To Cut Your Hydrangea to the Ground?
Hydrangea collectors will agree that these flowers are among the easiest to maintain once established. You can also freely decide on their pruning needs based on convenience. However, there are some essential pieces of information you need to know.
You don’t have to cut your hydrangeas to the ground. However, doing so can help them allocate their energy and resources to producing new shoots and flowers. Otherwise, they will have fewer and unruly blooms next flowering season.
It is also crucial to know that since this family of flowers has wide varieties, they essentially have different pruning or cutting requirements. As mentioned, you can do away with pruning, but many plants, including hydrangeas, grow better with occasional pruning.
Typically, varieties that bloom on new wood can benefit from being cut to the ground. On the other hand, old wood bloomers are better off left uncut. The latter variants can tolerate a bit of pruning to eliminate dead stems, but you must time the pruning appropriately.
Incorrect timing of pruning can cause a delay or significant reduction in the number of blooms in the next flower season.
I recommend minimal pruning on your wood bloomers. When necessary, prune them by the end of the blooming season, shortly before they form buds in late summer or fall. You can also prune in late winter to remove branches that died due to frost injury.
On the other hand, you must prune new wood bloomers in late winter or spring to remove branches damaged by the frost and encourage the growth of new shoots where flowers can bloom. Still, there are exceptions to these essential details.
How To Cut Different Hydrangea Varieties
When buying hydrangea from breeders, it helps to ask for varieties that grow best in your region. If possible, you can also ask for care and maintenance tips for more experience-based information that applies to your area.
If such options are unavailable, we will discuss below some general pruning information about common hydrangea varieties in the US.
Arguably the most popular hydrangea variety, Hydrangea paniculata is relatively easy to grow and maintain. Their flowers are more conical than globular in shape, giving them the nickname ‘panicle’ hydrangea.
This variety of hydrangea blooms on new wood and can benefit from some degree of cutting or pruning after they go into dormancy. You may cut them to the ground or shape them by pruning 30 – 50% of the branches.
You can start by cutting up to 50% of the plant’s length in the outermost branches and reducing the percentage as you go towards the center. It will give your plant a rounded appearance once the foliage and flowers grow back.
Ideally, you should prune your Hydrangea paniculata in late winter to early spring to encourage new growths and blooms by summer. Avoid pruning when the plant is still actively growing or blooming.
Here’s a video showing how to prune your hydrangea correctly:
Another variety that does exceptionally well when cut to the ground is Hydrangea arborescens. Like the paniculata, arborescens also blooms on new wood, and pruning it down to the ground helps it produce beautiful and bushier blooms during the flower season.
However, you must wait until the plant is established fully before pruning it to the ground. Ideally, you should wait two or more years until the plant successfully produces blooms. Pruning helps them have sturdier stems with bigger diameters that will enable them to hold the weight of the new flowers.
It is best to prune established arborescens to the ground late in the winter to remove dead branches and encourage new growth in spring. As they grow, they would make a vibrant, bushy hedge. You can then prune it once every one to two years to maintain its shape.
If you have a bigleaf hydrangea (Hydrangea macrophylla), you don’t need to prune it, except when you are trying to shape it to keep it looking neat during the blooming season. This variety blooms on new and old wood, allowing flexible pruning decisions.
Depending on the type of macrophylla, this species can grow 4-12 feet (1.2-3.6 meters) tall, making it somewhat challenging to cut off the branches after they have grown so tall.
If you want to tidy up or revitalize the mature plant, you can cut the branches injured by winter or frost, which is why your macrophylla may fail to produce plentiful and healthy blooms. The best time to do so is in late winter or early spring.
One of the varieties that bloom on old wood is Hydrangea serrata. It is similar to macrophylla but is relatively shorter at 2-4 feet (0.6 – 1.2 meters). This variety also tends to grow into a rounded bush. Pruning can help maintain its shape.
This variety can benefit from pruning after the blooming period, typically in August. You can also cut dead branches in early spring.
Here’s how to properly cut your Hydrangea serrata:
- In the fall, use sterile garden shears and cut the branches diagonally at a 45° angle.
- Like with most old wood bloomers, remember to cut the branches approximately ¼ inch (0.6 cm) above a bud, which will form into blooms next summer.
- If you want to maintain its shape, trim the outermost branches lower than the main trunk and central branches. Be careful not to cut off some healthy buds, as it may significantly reduce your blooms next summer.
- In spring, nip off any dead branches in the middle as they can negatively affect the number of flowers.
The oakleaf hydrangea (Hydrangea quercifolia) is another old wood variety. Its common name comes from its foliage which resembles an oak tree’s leaves and turns brown or orange in the fall.
This variety typically blooms until late in the summer. It is best to prune them in August before they form the buds for next year. However, if your plant has plenty of unruly branches growing in all directions, you may need to cut them to the ground regardless of the number of buds they have.
It may decrease the number of blooms next summer, but it will help ensure that the plant size and shape stay manageable.
Benefits of Cutting Hydrangea
Whether you cut them to the ground or prune just a few dead branches, cutting your hydrangea has many benefits. Here are some of them:
Cutting Hydrangea Can Increase and Improve Blooms
Paniculata and arborescens typically have more blooms when cut to the ground in spring because blooms grow on new growths. The shoots grow back quickly with proper care and can provide excellent support to the heavy fresh flowers.
Meanwhile, pruning old wood bloomers can help eliminate dead or unruly branches, which can interfere with the growth, quality, and appearance of new blooms.
Cutting Hydrangea Can Help Maintain Its Size and Shape
You would ideally plant hydrangeas in wide areas where they can get enough space to spread and grow. Some varieties can grow very tall and wide, requiring regular pruning to manage their size and shape.
If left uncut for many years, it may result in an unruly mess and require hard pruning to keep it under control.
Cutting Hydrangea Can Eliminate Winter-Damaged Shoots
Winter-damaged stems or branches may carry diseases or make the entire plant susceptible to secondary microbial infection. Cutting them will help protect and revitalize your plant.
Whether you have an old wood or new wood bloomers, cut the dead branches to the ground to help the plant focus on growing fresh, healthy shoots that can support the growth of new blooms in the coming years.
Hydrangeas typically live for several decades, so having fewer blooms in one year shouldn’t be a cause for concern that would prevent you from pruning your plants.
You don’t have to cut hydrangeas to the ground yearly, especially when you have old wood bloomers. Pruning hydrangeas is necessary only for the following reasons:
- To encourage the growth of new shoots and blooms among new wood blooming varieties.
- To remove damaged or dead branches.
- To control the size and shape of your plant.
It is also essential to know the proper timing to prune your hydrangeas based on the variety you have to avoid missing out on their beautiful blooms in summer.