#ProPlantTips: How to Prune Hydrangeas
#ProPlantTips: How to Prune Hydrangeas
Pruning By Type
We’ve all been there, looking at the remnants of last year’s hydrangea wondering, “Do I prune these back or leave them be?” It’s an especially confusing question because the answer depends on the type of hydrangea you have.
It is so important to know what kind of Hydrangea you have before you do any pruning. Some hydrangeas bloom on new growth and others will bloom on old wood. If you prune back the latter at the wrong time, you’ll be cutting off this year’s flowers!
It is probably easiest to break down the types of Hydrangeas and suggest pruning for each of the different types. Each group of Hydrangea includes some of the selections available from Nature Hills.
Panicle Hydrangeas (Hydrangea paniculata)
These are a woody and particularly hardy Hydrangea variety. They love the sun and are very forgiving, overall, needing little care from you. You can’t change the color of this group, but they offer quite the show, opening white, and aging to pink or red before turning brown in early fall and winter.
Pruning for Hydrangea paniculata shrub form and tree form should be done in early spring before new growth begins to grow. The best pruning method is to shorten up the length of last year’s stems by about 1/3 (which will reduce the size of the plant and remove last years blooms).
Leave the pruned shrub as an informal, irregular and somewhat rounded form. The same goes for tree forms. Prune in late winter or early spring but keep the overall rounded form. No more pruning is needed after the early spring prune.
These are a simple, easy and certainly rewarding group of Hydrangeas that every landscape should include. Their dried blooms offer unique texture throughout the winter and provide focal points when the rest of the garden is dormant.
Of all the varieties, these are the most commonly trained into trees. Create a show-stopping centerpiece by planting a tree form in your garden!
Our Favorite Shrub Forms:
Our favorite Tree Forms:
Oakleaf Hydrangeas (Hydrangea quercifolia)
Native to the southeastern United States, Oakleaf’s have panicle-shaped blooms that open white and age to pink and some of the new ones to red. This variety has gorgeous large oak leaf-shaped leaves (hence the name).
These woody Hydrangeas produce flower buds on last year’s stems so DO NOT SPRING PRUNE THIS GROUP! Oakleaf Hydrangeas will not flower if you spring prune the tips of the branches.
Light pruning to shorten branches as soon as they are done blooming can be done. You can also remove the largest, fattest branches right down to the ground to allow new shoots to grow from the ground keeping the plant blooming wildly on those new shoots.
Smooth Hydrangeas (Hydrangea arborescens)
Smooth Hydrangeas, or Hydrangea arborescens have that much sought after mophead blooms in either white, light green or tones of pink and red. They’re native to the United States and are known for their hardiness and easy to care for nature.
You should prune these Hydrangeas by cutting all of the stems right down to the ground in winter or early spring each year before they start to grow. Smooth Hydrangeas make incredible new flowers on shoots that come from the ground each year.
Some gardeners like to leave a foot or so of last year’s stems to help support the new shoots as they begin to grow but that is up to you. Super easy, non-invasive shrubs that you simply cut off each spring and sit back and enjoy the show. Many of the newer selections are reblooming.
Bigleaf Hydrangea (Hydrangea macrophylla)
Perhaps the most popular and widely known of the Hydrangeas, Bigleaf's blue or pink blossoms are coveted. Big leaf Hydrangeas are blue or purple in more acidic soil, and the same plant will be pink to red in higher soil pH.
These are true statement pieces, though a little tougher to grow. It’s important to know the care basics for the cultivar you pick. Make sure to read our #ProPlantTips on each Hydrangea’s page so you know exactly what its needs are.
Many of the selections in this huge group of Hydrangeas bloom on last year’s stems, so DO NOT PRUNE IN FALL, WINTER OR SPRING, just wait until they bloom.
Pruning for Bigleaf Hydrangeas is best done right after they bloom. In colder areas, there may be some winter damage, so sit back and wait until the plant is just starting to grow. Then remove the dead tips and the old flower heads, and leave the live portion of the stems in place.
To give your Bigleaf Hydrangea the best shot in colder zones, we suggest adding a 3-4 inch layer of arborist chips or mulch around the base of your plant. This helps protect the roots from the worst of winter’s cold temperatures along with summer’s hot. Plus, you’ll find mulch conserves water by helping to maintain moisture and reducing weeds.
- Endless Summer® The Original Bigleaf Hydrangea
- Grateful Red Hydrangea
- Summer Crush® Bigleaf Hydrangea
- LA Dreamin'® Hydrangea
Nature Hills’ selection of Hydrangeas continues to evolve. We’re always adding new selections with more flowers, smaller plants, and reblooming capabilities – all the things that keep bringing Hydrangeas into the limelight.