The Mountain Hydrangea, or Hydrangea serrata, is a deciduous shrub with a rounded shape that is native to Japan and Korea. It blooms from early to late summer with beautiful lacecap flowers in flattened clusters. Its flowers and leaves are smaller than those of the Bigleaf Hydrangea (Hydrangea macrophylla), but it has a more polished habit. The exquisite blossoms of some varieties, which are produced in large quantities, have the remarkable habit of changing color three to four times per season. This captivating process keeps your summer garden from getting stale.
- Mountain hydrangeas typically reach heights and widths of 2-4 feet (60-120 cm).
- Zones 6 through 9 are hardy, Mountain hydrangeas are more susceptible to cold than their mopheaded siblings are, but they are less subject to spring frosts. All year long, a thick covering of mulch is welcome (shredded bark, peat or compost ). This will control weed growth, hold onto moisture, and lessen soil temperature swings.
- Mountain hydrangeas thrive in rich, medium-moisture, well-drained soils and prefer partial shade. They can only grow in full light if the soil is continually moist. Compared to Bigleaf Hydrangeas, they are less resilient and tolerant of windy, hot, and dry conditions.
- According to the pH of the soil, the majority of Mountain Hydrangeas have the additional appeal of changing color. These species can grow blue blooms in highly acidic soils, whereas pink flowers can grow in somewhat acidic soils. If you want your Hydrangea’s blossoms to be a different hue, you can amend the soil with aluminum sulfate to make them bluer or with lime to make them pinker.
- No significant pest or disease problems. Keep an eye out for leaf spots, mildew, bacterial wilt, and bud blight.
- Perfect for container and foundation plantings. grouped in a protected area or used as a decorative plant.
- After flowering, Mountain Hydrangea stems should be pruned by being cut back to a pair of sound buds. In the early spring, remove weak or winter-damaged stems.
Are mountain hydrangeas pruned?
Mountain hydrangeas flower on both old and young wood, thus pruning is not recommended. Never cut or trim them back, besides to get rid of any dead wood (especially in spring in cold climates).
My mountain hydrangea should I deadhead it?
To keep your hydrangeas looking their best and promote the development of new flowers, deadhead regularly during the blooming season.
But in mid- to late-fall, stop deadheading hydrangea shrubs, leaving any spent blooms in situ. This not only adds beauty to the winter landscape but also guarantees that the buds that will bloom the following spring are not removed.
When should hydrangeas be pruned?
Depending on which group the plant belongs to, the timing and extent of pruning are determined:
Advice on Pruning for Group 1:
- As the days get shorter and the weather gets colder in the late summer and fall, buds for the following year’s blooms start to form.
- Typically, removing dead, diseased, or damaged branches is all that is required to preserve shape, size, and a healthy plant. Otherwise, gentle pruning ought to be practiced.
- In the summer, trimming should begin as soon as flowering ends, but no later than August 1. Pruning should not be done in the fall, winter, or spring because you risk removing fresh buds.
- Tip-pruning the branches in the spring as the leaves begin to appear can promote more numerous, smaller flower heads as opposed to fewer, larger flower heads.
Advice on Pruning for Group 2:
- On the growth of the current year, flower buds form.
- Early in the spring, as the leaves are starting to emerge, prune.
- Just above a node, prune branches back by half to a third.
- After that, prune any fragile or spindly branches.
- Minimal trimming encourages huge, strong bushes with many of tiny flower heads in H. arborescens. Hard pruning between 12 and 18 inches from the ground, or even all the way down, will result in fewer but larger flower heads that may flop if unsupported.
- For H. paniculata, remove the surrounding smaller wood while leaving the larger stems in order to establish a sturdy foundation.
Pruning may be connected to flower head size. Shoots will grow more vigorously and flower heads will be bigger and fewer with more rigorous trimming. Smaller but more numerous flower heads may result from less aggressive or tip pruning.
Consideration of hydrangeas’ mature size is the best piece of advise. Place them in a location where they won’t outgrow and won’t need a lot of pruning to keep them in check. Hydrangeas don’t need to be pruned precisely or often; as long as dead wood is removed, they will remain healthy and continue to develop and bloom.
Can mountain hydrangeas grow on both new and ancient wood?
Hydrangeas come in two varieties: those that bloom on aged wood and those that bloom on young wood. The majority of bigleaf, mountain, oakleaf, and climbing hydrangeas blossom on ancient wood. For the following season, they begin to create buds in the late summer and early fall, and they keep those buds through the winter. Therefore, pruning these plants once the buds form and at any time up to the next summer will result in few, if any, flowers. The same trimming guidance is applicable to hydrangeas that are reblooming because they retain buds from the prior year. I often prune oldwood hydrangeas to manage height at the end of July or the beginning of August. This allows the plant enough time before winter to develop buds, grow, and harden off. I advise letting the plant tell you what is alive or dead if you wish to cut off dead wood in the spring. When the spring leaves appear, cut the stems above the new growth, getting rid of any that have no signs of vitality.
Hydrangeas that bloom on new wood
The most reliable and cold-resistant flower producers in the Hydrangea genus are those hydrangeas that flower on fresh wood, such as panicle and smooth varieties. These hydrangeas bloom and set buds at the same time, protecting their buds from the dangers of winter. Pruning in the late fall or early spring won’t hinder bloom growth. Identifying whether your hydrangea blooms on old wood or fresh wood simply by looking at it can be very challenging. Maintaining plant tags and being aware of the species you’re working with is preferable.
The founding partner and co-owner of West Kingston, Rhode Island-based wholesale nursery Morningstar Nurseries is Bob Aube.
Local garden centers sell many of the kinds mentioned in this article or can special order them for customers. The following mail-order nurseries may have them if you don’t have access to any nearby options:
What occurs if hydrangeas are not pruned?
If and when you prune is the key to happy, healthy hydrangea flowers. Of course, fertilizing and offering the ideal environment have a lot to recommend them. However, if you don’t prune properly, your efforts will be in vain. Deadheading is not the same as trimming. Pruning refers to more drastic cutting to preserve shape or remove dead growth. However, feel free to discard spent blossoms or cut fresh ones to use in arrangements.
Hydrangeas can bloom on either fresh wood or old wood, depending on the species. The wood from which they blossom determines whether and when to prune.
Old wood-blooming hydrangeas do not require pruning and benefit from it. They’ll blossom more abundantly the next season if you leave them alone. But feel free to deadhead or gently thin. Just keep in mind that while new growth may appear, it won’t bloom until the following season. In our region, four different species blossom on aged wood. Additionally, they are not limited to the hues displayed here.
Climb using suckers. On your wall or trellis, resist the desire to remove the dormant growth.
The flower heads are more conical in appearance, and the leaves are large and resemble oak leaves. It’s a pleasant surprise for a hydrangea when its leaves turn reddish-orange in the fall.
They are very comparable to lacecap types, but smaller and with more compact leaves.
Pruning should be done in late winter or early spring on hydrangeas that bloom on new wood. Trim back to two feet to prune to shape. The next season’s blossoms are produced by strong, fresh growth that is encouraged by trimming. In our region, there are two types that bloom on fresh wood. They are also not restricted to the colors displayed.
Oakleaf variants are not included in cone-shaped blooms. Keep the blooms on throughout the winter to provide interest; even dried out, they are quite lovely.
regarded as a wild kind. They often have smaller blooms and leaves than Bigleaf variants and are completely white. They enjoy full sun and can grow very tall.
Knowing whether or when to prune now will help you avoid the disappointment of a hydrangea that doesn’t blossom. Don’t forget that a robust shrub will produce more gorgeous blossoms if it has well-draining soil and good organic fertilizer. Come on in, and we’ll show you where to go to develop your green thumb.
How can a mountain hydrangea be prepared for winter?
Winter winds and cold temperatures both have the potential to be fatal. This catch-all phrase simply denotes plant dying over the winter. The plant may perish due to the low winter temperatures or from drying out brought on by the winds.
Since hydrangeas become dormant in the winter, winter damage to hydrangeas can not become apparent until spring. If your hydrangea doesn’t produce any green shoots in March or April, it could be your first indication of harm.
Protecting the shrubs from winter’s wrath is necessary to avoid winter kill in hydrangeas, which includes the young buds on the plants. Laying down a heavy layer of mulch over hydrangeas’ root zone is a wonderful place to start with winterizing them. For this, straw works wonderfully.
Use a wire cage to enclose the shrub or construct a cage around it using sturdy posts and chicken wire for even better protection. Wrap the cage in burlap or insulating material. Additionally, you should give the plant a lot of water right before the ground freezes.
Should old hydrangea blossoms be removed?
Myers advises leaving the dried blossoms on your hydrangeas if you’re looking for an easy way to spice up your winter yard. Bigleaf hydrangeas produce their final rush of flowers in the fall, so to enjoy the dried blossoms all winter long, stop deadheading at that time. To aid in the production of healthy buds in the spring, these can be removed.
What kind of flowers are mountain hydrangeas?
The least common mophead is the mountain hydrangea (macrophylla). These deciduous shrubs are indigenous to Japan. Zones 5 to 9 are suitable for the hydrangea serrata. Compared to other mophead hydrangeas, mountain hydrangeas are usually more compact and smaller.
Like other macrophylla, the leaves are serrated and dark green. Since the leaves contain the natural sweetener phyllodulcin, they are frequently used in tea. The tea is referred to as amacha in Japan and sugukcha in Korea. In Japan, macha is used to commemorate Buddha’s birth. This tea is sometimes referred to as “tea of heaven.”
With smaller florets in the center and larger florets surrounding them, the flowers resemble lacecap hydrangeas more. Depending on how acidic the soil is, the blooms are either blue or pink. In more acidic soils, the blossoms will be blue, whereas in alkaline soils, they will be purple to pink.
Cut back these shrubs in late winter before new growth begins
Shrubs that flower on young wood typically start blooming later than old-growth bloomers, beginning in June and continuing until the first frost, because they need to grow and set buds the same year that they bloom. As long as you avoid trimming when the flower buds are opening, these shrubs are understanding if it is not done at a specific period.
1. Trim the flowers all the way back for larger blooms.
These bushes can be completely removed from the ground in late winter or the beginning of spring. If cut severely like this every year, smooth hydrangeas will produce much larger flowers, but many gardeners prefer smaller blooms on stronger stems.
2. Maintain an old growth foundation to lessen flopping
Especially after watering from above or after a heavy storm, the branches of some hydrangeas frequently topple over from the weight of their blooms. Cutting the stems to a height of 18 to 24 inches will help to reduce this flopping by creating a strong framework for fresh growth.
Janet Carson is the University of Arkansas Cooperative Extension Service’s horticulture specialist.
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Is the wood on my hydrangea old or new?
Some hydrangea species, known as “old wood,” bloom on growth from the previous year. The flower buds that will bloom in the upcoming summer are present in this old wood. We would have a plant without flowers this year if we pruned in the winter or spring because we would lose the flower buds. As a result, many cultivars undergo pruning following summer blooming.
The young growth that appears in the springtime bears flower buds when hydrangeas that bloom on new wood are present. These plants can be clipped in late winter or early spring before new growth starts because the buds are not present during the winter months.
Do I need to remove the Brown hydrangea leaves?
If newly emerging hydrangea leaves or flower buds are exposed to a late-spring frost or chilly winds, they will turn brown. A unexpected cold spell can harm the newly emerging buds and leaves, which are exceptionally delicate and susceptible to injury. This can cause the buds to turn brown and wither away.
Naturally, hydrangeas grow in protected regions under trees that block chilly winds and produce a more stable microclimate that allows the young flowers to open up without facing a serious risk of frost.
Hydrangeas’ newly formed buds and leaves can become mushy and their leaves can turn brown when they sustain frost damage.
Since it is more exposed to the environment, the outermost growth is typically the one that suffers from the worst damage.
Sadly, the harmed flower buds are therefore unable to bloom, and the freshly growing growth is probably not going to recover.
Frost damage to hydrangea flower buds and foliage is more common in exposed areas, so plant or move your hydrangea to a more protected area of the garden, close to your house, or close to some other plants and hedges.
Particularly hedgerows are great wind breakers since they shield your hydrangea from the elements and might lessen the effects of frost.
There isn’t much you can do to save flower buds or younger leaves after they turn brown. As a result, prune back to healthy growth any growth that has been harmed by the frost.
In contrast to the flower buds on the plant’s outermost part, which are naturally less protected, hydrangeas frequently have growing flower buds farther down each branch. These flower buds typically survive a frost.
This implies that your hydrangea can still bloom, but much later and with fewer flowers emerging. With a little patience, you should still be able to enjoy some lovely blooms throughout the Summer.