Hydrangeas are primarily recognized as a source of summer color, but when left untrimmed until spring, their intriguing bark and flower heads may also add texture in the winter. Because of their generally coarse texture, they thrive in less formal gardens, perhaps at the property’s edge.
Hydrangeas can grow from three to fifteen feet tall and four to ten feet wide, depending on the species. They thrive on moist, fertile soil that receives full sun to partial shade. Long after the majority of shrubs have done blooming, hydrangeas produce huge white, pink, or blue panicles or clusters from June through August. Landscape plantings in Kentucky typically use four species.
KY Hydrangea SpeciesBig Leaf Hydrangea
The most popular variety of hydrangea in Kentucky is called Hydrangea macrophylla, or Big Leaf Hydrangea. White, pink, and blue can be found in its substantial blossoms. White cultivars stay white, but the availability of the micronutrient aluminum and the pH of the soil affect the color of pink or blue cultivars. Pink flowers are typically inspired by soil pH levels of 6 or above, whereas blue blooms are typically produced by soil pH ranges of 5.0 to 5.5.
In a greenhouse, specific Big Leaf Hydrangea cultivars are grown as potted plants in order to bloom in time for late-winter and early-spring events like Easter. These House Hydrangeas were chosen not for hardiness but for blossom size and simplicity of flower forcing. Without specific winter care, the majority of house hydrangeas planted in Kentucky landscapes won’t reliably produce flowers. The blossoms of the potted hydrangea are pink unless aluminum sulfate, which lowers pH and turns the flowers blue, is added to the potting medium or landscaping soil.
The majority of this species’ cultivars bloom on wood from the previous year. The blooms for the upcoming season will not survive if temperatures fall too low. With probable lows of -10 degrees, Kentucky is classified as zone 6. On occasion, extremely low temperatures destroy shoots or flower buds, preventing any flowering that year. Breeding efforts to enhance flowering characteristics have produced a number of new choices, such as “Endless Summer,” that will blossom on the growth of the current season and produce blooms even if late spring frosts damage the flower buds.
KY Hydrangea SpeciesSmooth Hydrangea
Large, white blossoms on new growth characterize Hydrangea arborenses, also known as the Smooth Hydrangea, which bloom every year from June through September. August will see a second flush of blossoms if the brown flowers are removed. It thrives in moist, well-drained soil with full sun to partial shade. In areas where the weather is typically hot and dry, some shade is optimal. This hydrangea can be used in smaller landscape locations because of its three to five foot height. There are a number of excellent cultivar options, but “Annabelle” is the most well-liked.
KY Hydrangea SpeciesPanicle Hydrangea
One of the bigger shrubs, Hydrangea paniculata or Panicle Hydrangea, can reach heights of six to ten feet and widths of six to ten feet, depending on the cultivar. In full sunlight, this plant will flourish. From June through September, enjoy the white to purplish-pink blossoms. When they start to turn brown or in the winter, blooms can be trimmed. This species’ “Limelight,” which has big, light green blossoms that develop to white, is a well-liked choice.
KY Hydrangea SpeciesOak Leaf Hydrangea
The Oak Leaf Hydrangea, or Hydrangea quercifolia, is a popular landscape plant for locations with part shade and is a native of the southeastern United States. It is renowned for its big, oak leaf-shaped foliage. With panicles that are three to four inches broad, the white to purplish-pink flowers range in length from four to twelve inches. There are many of fragrant flowers. The foliage changes to reddish, orange-brown, and purple hues in the fall, bringing more color to the environment. The Oak Leaf Hydrangea does best as a border planting in partial shade.
Growing Hydrangeas in Kentucky
Give these four common Kentucky hydrangea types a spot that will receive full sun to part shade to get the most out of your planting. Drought stress and scorching heat are lessened by afternoon shade. Don’t prune in the autumn. After the shrub has flowered in the summer, prune to give it time to develop new flower buds for the following season before winter arrives.
The book Hydrangeas for American Gardens by Michael A. Dirr, published by Timber Press, is a wonderful source for more information (2004).
Oldham County Horticulture Assistant Michael Boice contributed the writing. Lauren State, an assistant with the Oldham County Extension, edited the text.
KENPAI, Frank Vincentz, and Anne Norman all contributed photos. the Creative Commons Attribution license is used.
When is the best time of year to prune my hydrangeas?
The type of hydrangea you have will determine when to prune it. It is necessary to prune hydrangeas that bloom on new growth in late winter or early spring. Hydrangeas that flower on old, woody growth must be clipped after flowering in the summer.
The specialists at the seed and plant firm Thompson & Morgan state that most hydrangeas are clipped in early spring, ideally in February or March, with the exception of climbing hydrangeas, which are pruned in summer (opens in new tab).
The clearest indicator that your hydrangea is ready for trimming is when all of the seed heads have dried up and new, vibrant green buds have begun to emerge. When you notice those, you’ll know it’s time to prune, according to Lee Burkhill of Garden Ninja (opens in new tab).
Although many hydrangea varieties are pruned at the same time of year—late winter or early spring—the methods for each variety vary.
Do hydrangeas need to be pruned before winter?
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 much should hydrangeas be pruned back in the fall?
Trimming season for hydrangeas that bloom on new wood runs from late fall through early spring. This group includes smooth and peegee forms, which function well whether they are pruned lightly, to the ground, or not at all. In order to maintain a compact stature and luxuriant flowering, Peegee hydrangeas are frequently pruned into trees with one or two main stems that are between 15 and 30 feet tall.
Smooth hydrangeas can be pruned all the way to the ground; however, the more frequently they are cut, the less able their stems are to withstand the weight of their huge blooms. Smooth hydrangeas grow in mounds that are 3 to 6 feet tall and wide. When the plants are pruned to leave between 18 and 24 inches of growth, a woody base forms that helps the stems support the pompom blooms more effectively.
Should hydrangeas be pruned annually?
Only prune these hydrangeas in the summer after bloom, not in the fall. In August and September, old wood hydrangeas begin to form their bloom buds for the following year. It is advisable to delay pruning your hydrangeas until the following year if you don’t do it right away. If not, there won’t be any blossoms the next spring.
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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Should I remove the brown blooms on my hydrangea?
Your hydrangea shrubs’ blossoms appear to be withering or turning brown. No need to worry—this is merely a signal that it’s time to deadhead—remove the blossoms from the plant.
Deadheading hydrangeas doesn’t cause any damage to the plants at all. Flowering shrubs stop producing seeds when the spent blooms are removed, and instead focus their efforts on developing their roots and leaves. You will be doing your hydrangeas a favor by deadheading because this strengthens and makes plants healthier.
What occurs if hydrangeas are not deadheaded?
Deadheading too-tall hydrangeas can occasionally be challenging. Your other option is to keep them on if you don’t have the skills to reach spent flowers or all of the spent blooms. And you can do that without suffering too much harm.
Simply omit deadheading hydrangeas, and your plant won’t suffer. At least nothing major enough to need worrying about.
Your hydrangea might not produce as many or as large of blooms as it would have if the spent blooms had been removed. It will nevertheless continue to bloom.
Having said that, you can think about pruning hydrangeas that have gotten too tall in order to make them smaller and easier to handle.
This will make it simpler for you to maintain the tidy appearance of your hydrangeas. Additionally, it will make it simpler to remove spent blooms from plants and promote future blooms with greater vigor.
Do you prune hydrangeas in the spring or the fall?
Pruning is not typically thought of as one of the many gardening activities that may be done in the fall, despite the fact that there are several. It can be difficult to cultivate hydrangeas successfully in New Hampshire, and if you want your plants to blossom, there is frequently very little room for error in pruning.
Wait until Spring to prune hydrangeas
In New Hampshire, hydrangeas come in a variety of kinds, and each one has quite distinct growth patterns and pruning needs. Some plants only produce flowers on fresh growth, while others mostly produce flower buds on older wood. In any case, it is better to postpone all hydrangea pruning until spring. Hydrangeas, as with all other trees and shrubs, go dormant in the fall. Not much new growth is produced by them until the next spring. As new growth is more vulnerable to harsh cold at the location of wounds, plants that have been trimmed now run a higher risk of winter damage. Additionally, fall pruning may lessen the quantity of June blooms.
Considerations for pruning hydrangea species commonly grown in New Hampshire gardens
The gigantic blue mopheads or lacecaps known as bigleaf hydrangeas (Hydrangea macrophylla), which are familiar to most gardeners, form their flower heads at the tips of stems on old wood from the previous year. Although lower buds along the stem have the capacity to grow blooms as well, the hydrangea’s blossoming potential is decreased if those buds are died or damaged throughout the winter. Wait until new growth sprouts in the spring before pruning your bigleaf hydrangeas. Approximately 1/4 inch above the first group of live buds, prune the plant. A hint: the interior of living stems will be green, whereas the interior of dead stems will be brown. Cut completely dead stems flush with the base.
The three other hydrangea species that are frequently planted in Fresh Hampshire—oakleaf (H. quercifolia), panicle (H. paniculata), and smooth—all bloom on new growth. Before the emergence of the leaves in the late winter and early spring, remove wasted flowers and prune the plant to improve its general structure and habit.
In conclusion, there are a ton of other activities you can engage in to stay occupied in the garden during fall. Save the spring for hydrangea pruning.
In the spring, how far back should hydrangeas be pruned?
You can prune hydrangeas paniculata and aborescens more severely without losing this year’s blossoms because they bloom on new wood. Although pruning is not necessary, if it is not done the plant will grow taller, with the majority of its flowers at the top.
Cut back to a healthy framework
Trim the previous year’s growth back to a strong framework that is between 30 cm and 60 cm high in the early spring. On each stem, prune to just above a pair of sound buds. For large flowers, prune back to the lowest healthy buds; less firmly for a more natural appearance or a higher plant.
Watch Monty Don describe the many hydrangea trimming techniques in spring: