Should You Cut Back Hydrangeas?

Ever stare at your hydrangeas, wondering if cutting them back will help or hurt them?

Knowing when—or if—you should prune can be the difference between stunning blooms and a sad, flowerless bush.

In this guide, we’ll break down exactly when it’s time to cut back hydrangeas, how to do it right, and why some types need different care than others.

Hydrangeas and Their Growth Cycle

Hydrangeas are known for their large, showy flowers, which range in color from shades of blue and purple to pink and white, depending on the soil's pH level.

They are relatively low-maintenance, but their growth habits differ depending on the variety. The most common types include:

1. Bigleaf Hydrangea (Hydrangea macrophylla)

This variety blooms on old wood, meaning it flowers from the growth of the previous year.

2. Panicle Hydrangea (Hydrangea paniculata)

Panicle hydrangeas bloom on new wood, which grows during the current season.

3. Smooth Hydrangea (Hydrangea arborescens)

Smooth hydrangeas also bloom on new wood, producing flowers on fresh growth each year.

The type of hydrangea you are growing determines when and how it should be cut back.

Pruning hydrangeas not only encourages new growth but also helps maintain the plant's shape and prevent overcrowding.

Failure to prune may lead to fewer blooms or a less aesthetically pleasing shrub.

Why Hydrangeas Need to Be Cut Back

Cutting back hydrangeas is an essential part of their care.

Regular pruning encourages healthier, more robust growth. It also promotes better flowering in the next growing season.

Pruning removes dead, damaged, or diseased wood, preventing the spread of disease.

Lastly, it helps maintain the plant’s shape and size, preventing it from becoming overgrown and unwieldy.

Step-by-Step Instructions for Cutting Back Hydrangeas

1. Identify the Type of Hydrangea

Before you begin pruning, it's important to identify the type of hydrangea you are working with. This will dictate whether you prune in the early spring, late summer, or fall.

Bigleaf hydrangeas should be pruned right after they finish blooming in late summer, while panicle and smooth hydrangeas should be pruned in late winter or early spring.

2. Gather the Proper Tools

To ensure a clean cut and minimize damage to the plant, you'll need a pair of sharp pruning shears, gloves to protect your hands, and possibly a larger pruning saw if dealing with thicker branches.

Clean your tools with rubbing alcohol before use to reduce the risk of introducing disease to the plant.

3. Start by Removing Dead or Diseased Wood

Inspect the plant for any dead, damaged, or diseased branches. These should be removed first, cutting them all the way back to the base of the plant.

This allows more energy to be directed to healthy growth and encourages better air circulation within the plant.

4. Cut Back Old Blooms

For bigleaf hydrangeas, you should prune away the spent blooms immediately after they fade.

Cut back to the first set of healthy buds below the bloom. This ensures that the plant will produce new flowers next year, as these varieties bloom on old wood.

5. Trim for Shape and Size

After deadheading and removing any damaged wood, you can begin shaping the plant. Trim branches that extend beyond the plant's desired size.

For hydrangeas that bloom on new wood, such as panicle or smooth hydrangeas, you can cut back the plant by up to one-third of its size.

This encourages more compact growth and larger flowers.

6. Cut Back Hydrangeas That Bloom on New Wood

For hydrangeas that bloom on new wood, such as panicle or smooth varieties, pruning can be more aggressive.

Cut the branches back to about 12-24 inches above the ground in late winter or early spring, before new growth begins.

This promotes vigorous growth and ensures larger blooms in the coming season.

7. Clean Up and Mulch

Once pruning is complete, gather up the clippings and dispose of them. Removing plant debris helps prevent the spread of pests and diseases.

Consider adding a layer of mulch around the base of the plant to help retain moisture and protect the roots during winter.

8. Monitor the Plant’s Progress

After cutting back your hydrangeas, keep an eye on the plant to ensure it is recovering well.

New growth should start to appear in the spring, and your plant should look fuller and healthier as the growing season progresses.

If you notice any signs of disease, such as discolored leaves or wilting branches, treat the plant promptly to prevent further damage.

Can Hydrangeas Be Cut Back to the Ground?

Yes, certain hydrangeas can be cut back to the ground, but it's important to understand which varieties tolerate this method.

Smooth hydrangeas (Hydrangea arborescens) and panicle hydrangeas (Hydrangea paniculata) can generally be cut back to the ground without harming the plant.

Since these varieties bloom on new wood, cutting them down in late winter or early spring encourages vigorous growth and larger blooms in the upcoming season.

However, bigleaf hydrangeas (Hydrangea macrophylla), which bloom on old wood, should not be cut back to the ground as doing so will likely prevent them from flowering the next year.

Instead, selective pruning is recommended to preserve the blooms.

How Do You Cut and Regrow Hydrangeas?

To cut and regrow hydrangeas, you can propagate them using stem cuttings.

Choose a healthy stem from the plant that has no flowers and is about 4 to 6 inches long.

Cut just below a leaf node (where a leaf meets the stem) and remove the lower leaves, leaving only the top set of leaves.

Dip the cut end in rooting hormone and place the cutting in a pot filled with a mixture of perlite and peat moss or any well-draining potting soil.

Keep the soil moist and place the pot in indirect light. Within a few weeks, roots should begin to form, and once the cutting is well-rooted, you can transplant it into the garden or a larger pot to continue growing.

What Is the Best Time of Day to Cut Hydrangeas?

The best time of day to cut hydrangeas is early in the morning or late in the afternoon.

During these cooler parts of the day, the plants are well-hydrated, and the blooms are at their freshest.

Cutting hydrangeas during the hottest hours can cause the flowers to wilt quickly due to heat stress.

By harvesting hydrangeas in the morning or evening, you help preserve their vibrant appearance and prolong their vase life.

How Long Do Hydrangeas Last?

Hydrangeas can last for many years, with proper care and maintenance.

Most hydrangea varieties are perennial, meaning they come back year after year, typically living for decades if planted in the right conditions.

The individual blooms of hydrangeas can last several weeks, with some varieties holding their flowers from early summer through the fall.

After they bloom, hydrangea flowers often fade but can still be left on the plant for visual interest through the winter months.

In Closing

Pruning your hydrangeas is a crucial task that ensures your plants remain healthy, vibrant, and full of beautiful blooms.

By understanding the specific needs of your hydrangea variety and following proper pruning techniques, you can encourage optimal growth.

Enjoy an abundant display of flowers in your garden year after year!