Pruning your hydrangea is an essential part of making it grow well and beautifully in your garden or front yard. Read here how to prune which type of hydrangea, how and when.
Hydrangeas have been very popular garden plants for decades. Older varieties add sentimental charm, and new hydrangea shrubs can bloom from mid-summer to fall. Hydrangea flowers are now available in an even wider variety of colors, including bright blue, deep red and light green. These versatile shrubs will thrive in sandy coastal soils as well as shady woodland areas and almost everything in between.
In general, hydrangeas need minimal care. The only thing you have to do well is prune the hydrangea. While many hydrangeas have interesting leaves and bark, most are grown for their large, showy blossoms. If your hydrangea doesn’t bloom for a season, it is usually for one of three reasons: they didn’t get enough sun, an early frost or cold spell killed the buds, or they were pruned at the wrong time. How and when to prune your hydrangea depends on which type you have.
What kind of hydrangea do you have?
There are many different types of hydrangeas. When pruning, you should pay particular attention to one characteristic, which is whether it grows and flowers on old or new wood . Most hydrangea species grow on old wood, with the flowers growing on branches that were formed in the previous year. Hydrangea species that grow and flowers on new (young) wood, the flowers and branches that the hydrangea formed this year are formed.
In general, varieties that bloom on old wood should be pruned immediately after flowering. And those that bloom on new wood should be pruned before new growth begins in the spring.
Always remove dead, damaged, or diseased stems as the first step during routine pruning. When cutting back stems, cut back to just above a few healthy buds. Stems damaged by winter can be cut back to live wood.
What do you need?
All you need to prune a hydrangea is a good bypass pruner.
Prune hydrangea on old wood
Do you have a hydrangea on old wood? Then prune it in two steps:
Pruning a hydrangea on old wood is best done after the winter in March or April. That way you also have a nice full plant in winter. Moreover, any new shoots will not freeze. Cut the faded flowers to just above the grown buds.
After the faded flowers have been cut away, get to work with the old branches. Trim off about a third of the old branches to 10cm above the base of the plant. Go for branches that overhang the most on the outside of the plant. You can also go for the highest branches. Flowers will grow on the remaining branches this year.
Do you like smaller hydrangea shrubs better? Then you can also keep it compact by cutting half of the old branches to 10 cm above the base of the plant. No flowers will grow on this. In the following year you can do the same with the other half of the Hydrangea. You keep repeating this alternating pattern every year, so that your hydrangea stays nice and compact.
Bulbous garden hydrangea
The bulbous garden hydrangea often has flowers whose color changes with the pH of the soil: blue in acidic soil and pink in alkaline soil. However, there are also a few varieties that simply remain white. The leaves are coarsely serrated and glossy dark green. bulbous garden hydrangeas set their flower buds from late summer to early fall. So, pruning in the spring or even late in the fall removes the flower buds and the chance of blooms for that season.
To keep the hydrangea looking neat, the dead flowers can be cut off. When most of the flowers have finished blooming, it is time to prune. Selectively prune the dead and weaker stems, both old and new, with bypass pruning shears. But don’t prune all branches, as this is what will continue to bloom as the new growth matures.
The Hydrangea quercifolia is perhaps less well known than the other hydrangea species, but that does not make this type any less beautiful. The leaf of Hydrangea quercifolia is reminiscent of the leaf of an oak, hence the name quercifolia. It is recommended to prune the Hydrangea quercifolia minimally. Because the flower heads are formed under the old faded flowers, pruning does not promote flowering. It is best to remove the weakly growing shoots and dead branches just above the ground when you notice that the plants are aging.
The mountain hydrangea, or Hydrangea serrata, is native to the mountains of Japan and Korea. Hence, this type is particularly hardy. They are a lot more compact and are available with umbel-shaped flowers and spherical flowers in different colors. This plant is sometimes confused with Hydrangea macrophylla because of their similar flowers. However, this type does not have the large leaves of Hydrangea macrophylla.
Flowering takes place on old wood and the plant’s pruning needs are minimal. After it blooms, prune and cut flowering stems back to a few healthy buds. Prune unhealthy stems down to the ground in early spring.
The stunning climbing hydrangea, the Hydrangea anomala petiolaris, is the type you see slowly rising up a tree or other support. It is a vine, not a shrub, and generally requires little to no pruning. This plant blooms on old wood from the previous season.
Once established, climbing hydrangeas can grow quite vigorously and require occasional late winter pruning to set boundaries for the season ahead. Neglected, overgrown vines can be cut to ground level in early spring to rejuvenate the plant.
Prune hydrangea on young wood
Hydrangea on young wood is very easy to prune in one size. The best time to do this is in the spring in March or April. Use the bypass pruning shears to trim the old branches to about 10 cm above the base of the shrub. The hydrangea will form new branches on which flowers will appear that will bloom this year.
The Hortensia ‘Annabelle’ are also very popular garden plants, characterized by beautiful large, spherical, white flowers. This type of hydrangea usually has no problems blooming, although the white flowers are not as showy as we normally expect from hydrangeas. It is a round shrub with leaves that are slightly rounded with a pointed end, paler at the bottom than at the top.
This shrub blooms on new branches. Thus, pruning should be done in early spring to ensure adequate growth for flowers. Remove any branches injured or killed in winter and lightly trim other branches to shape the plant. If you think that your hydrangea bush is getting too big, remove some of the branches, including will, from the ground.
Hydrangea paniculata ‘Grandiflora’
This is the most common hydrangea variety. They are also called the Panicle Hydrangea or Schapenkophortensia, and feature huge snowball-shaped flower clusters in mid to late summer. The flowers start out white and slowly turn pink, dry and stay on the plant long after the leaves have fallen.
Flower buds occur with new spring growth. A light pruning of individual stems in late winter or early spring will not only keep the plant from becoming overgrown, but will also promote healthy growth and flowers. During the growing season, you can remove the overgrown flowers and prune the overall shape of the plant as soon as the flowers become less attractive.