- Climbing Hydrangea Won’t Bloom – When Does Climbing Hydrangea Bloom
- When Does Climbing Hydrangea Bloom?
- Tips on Getting Climbing Hydrangeas to Bloom
- Garden Fundamentals – become a better gardener
- Why do Hydrangea Not Flower
- Lack of Fertilizer
- Too Much Fertilizer
- Water Issues
- Sudden Cold Snap
- Too Young
- Not Enough Sun
- Improper Pruning
- Winter Dieback
- The Endless Summer Disappointment
- Climbing Hydrangea Care Guide: How to Grow Climbing Hydrangeas
- Climbing Hydrangea Care
- Climbing Hydrangea H. petiolaris
- Hydrangea Care Questions and Answers
- How to Grow a Climbing Hydrangea
- Where and How to Grow
- Soil, Feed, and Water
- Temperature and Humidity
Climbing Hydrangea Won’t Bloom – When Does Climbing Hydrangea Bloom
Climbing hydrangeas have charming lacecap flowerheads made up of a disc of tiny, tightly packed flowers surrounded by a ring of larger blossoms. These lovely blossoms have an old-fashioned appeal, and when seen on a background of large, lush vines they are stunning. This article explains what to do when your climbing hydrangea fails to bloom.
When Does Climbing Hydrangea Bloom?
Climbing hydrangea blooms in late spring and summer. After a season or two comes and goes without a bloom in sight, gardeners may become worried about their vines. Take heart, because in most cases, there is nothing wrong. These vines are notoriously slow to become established and produce their first flowers. In fact, several seasons may come without blossoms. Rest assured that they are worth the wait.
Tips on Getting Climbing Hydrangeas to Bloom
If you become concerned about your climbing hydrangea when it fails to flower, take a look at this checklist of potential problems:
A late frost can damage buds that are on the verge of opening. You may want to try providing protection when a late frost threatens. A tarp or blanket thrown over the vine is enough to protect the plant from a light frost.
Vines that run along the ground won’t bloom. Attach the vines to a strong supporting structure.
Branches that stray from the main part of the plant use energy and don’t add to the appearance of the vine. They also add lopsided weight that may pull the vine away from its supporting structure. Remove them back to a main branch so the plant can focus its energy on upward growth and flowers.
When a climbing hydrangea won’t bloom, it’s sometimes the result of too much nitrogen fertilizer. Nitrogen encourages hydrangeas to put on a lot of dark green foliage at the expense of flowers. One to two inches of compost applied in a layer over the soil contains all the nutrients a young hydrangea vine needs. Once it’s established and growing well, you don’t need to fertilize at all. Lawn fertilizer is high in nitrogen, so keep it away from your hydrangeas.
You’ll have a hard time getting climbing hydrangeas to bloom if you’re pruning at the wrong time of year. The best time is immediately after the blossoms begin to fade. The buds for next year’s blossoms begin to form about a month after the flowering period. If you prune late, you’ll be clipping off next year’s blooms.
Garden Fundamentals – become a better gardener
Why does my hydrangea not flower? This most commonly asked question about hydrangeas, especially in colder climates. The answer is not always a simple one but I’ll try to answer the question in this post.
Reasons for not flowering depend very much on the type of hydrangea you are growing. It is therefore important that you know the type. Have a look at Hydrangea Identification to find out which type you have.
Hydrangea paniculata ‘limelight’, If you select the right hydrangea it will flower reliably, by Robert Pavlis
Why do Hydrangea Not Flower
The following is a list of some of the reasons for getting few or no flowers on your hydrangea.
A common myth is that fertilizer will make a plant flower but this is rarely the problem. If your plant is growing and looks healthy it has enough nutrients to flower. Whatever you do, don’t start throwing fertilizer at your hydrangea.
Bloom Boosters do not work. See Bloom Boosters – Fertilizer Nonsense #5, to understand why.
Lack of Fertilizer
A lack of fertilizer is almost never the cause for non-flowering. In fact, over fertilizing is probably a more common problem.
Shrubs in the landscape do not normally need to be fertilized. In 10 years I have never fertilized one of my shrubs.
Get a soil test done if you feel there is a nutrient deficiency in your soil. Then add the fertilizer you need – not something you don’t need. To better understand how to fertilize properly have a look at Fertilizer Nonsense #3 – All Tomatoes Need The Same Fertilizer.
Mulch with wood chips or compost, to provide a slow steady feed for all your shrubs.
Too Much Fertilizer
Too much nitrogen will result in lots of large leaves and few flowers (ref 1).
Too much or too little water can prevent flowering.
The idea that hydrangeas need lots of water is a myth. They do not need any more water than other types of shrubs. Water well during the first year and then treat them just like other shrubs. H. macrophylla and H. quercifolia do enjoy more moisture but they don’t need to be grown wet.
My hydrangea rarely get extra water. They need to live on what nature drops on them and they do quite well. You may need to water more in warmer or drier climates – just like other shrubs.
Sudden Cold Snap
Hydrangeas are slow to get conditioned to cold weather in the fall and they come out of hibernation early in spring. This means that flower buds are easily damaged by a sudden cold spell in fall or a cold snap following warm weather in spring. Buds that are damaged by cold will not open, or open improperly.
Buds below the snow line are protected from cold weather and it is common to see shrubs bloom on just the lower branches. The buds on the upper branches don’t open because they were killed off by cold weather.
Bud kill due to cold is only a problem for hydrangea that form their buds on old wood. These plants form buds in mid-summer and early fall for flowering the following spring. This group includes H. macrophylla, H. serrata and H. quercifolia. The climbing hydrangea, H. petiolaris, also forms buds on old wood, but the buds seem quite winter hardy even in zone 4.
H. arborescens, and H. paniculata form buds on new wood in late spring for flowering the same summer. The buds on these types of hydrangea are rarely affected by cold weather.
Each type of hydrangea needs to reach a certain age and size before it will flower. It might have been flowering in the pot when you bought the plant, but the transplanting process sets it back. It may need a year or two to establish itself and become a healthy plant.
Where the above ground growth gets killed off each winter, hydrangea may have trouble getting big enough to flower.
Most of the bush hydrangea bloom on fairly young plants, but the climbing hydrangea can take many years before it will flower. There is nothing you can do except wait.
Not Enough Sun
Do hydrangea prefer sun or shade? It really depends on both the type of hydrangea and the climate.
The following is a general guide.
In US climatic zones 6 or colder:
- All hydrangeas can take full sun provided they have enough moisture.
In US climatic zones 7 and warmer:
- Some shade should be provided for H. macrophylla, H. serrata, H. petiolaris and H. quercifolia. The preference for H. quercifolia is full shade. H. arborescens can take full sun in warm climates but probably does best with some shade. H. paniculata can take full sun even if dry.
If your hydrangea blooms on new wood, is a good sized shrub and is not flowering, try to move it into more light.
If you prune at the wrong time of year and cut the buds off you will not get flowers – it is that simple.
Hydrangea that bloom on new wood should be pruned in late winter. Those that bloom on old wood should be pruned right after flowering which ensures that new buds have not yet formed.
It is a myth that hydrangea need hard pruning to flower. All of them will flower with no annual pruning.
In addition to the cold snap discussed above, buds and stems can also be killed by cold mid-winter temperatures. In colder climates it is quite possible to have the stems die back due to a cold winter and still have a live plant. The crown of the plant is hidden below ground and receives some protection from the soil.
Plant hardiness ratings apply to the crown of plants and not to buds. Most H. macrophylla are quite hardy in zone 5 and will survive winter just fine. The buds and old stems are not hardy in zone 5 and die off each winter. Such plants grow fine each year, but never flower. Unfortunately, because of their very popular blue flowers these hydrangea are regularly sold in zone 5.
H. serrata and H. quercifolia are also hardy in zone 5, but their flowers are not. They rarely flower in colder zones.
If your hydrangea is one that forms buds on old wood and you have winter dieback of the stems, you will probably not get any flowers.
The climbing hydrangea will flower in zones 4 and 5.
The Endless Summer Disappointment
People in the north desperately want to grow large blue mophead hydrangeas but winter kills off the buds. All this changed with the introduction of Hydrangea ‘Bailmer’, Endless Summer™.
Endless Summer blooms on both old and new wood. This is great news for us northerners. Even if the old wood buds get killed off, the plant will make new buds on new wood – or so the advertising would have you believe.
The reality is that this cultivar does very poorly in zone 5. It may be able to flower on new wood, but it rarely does. The internet is full of people wondering why this miracle plant is not performing – what are they doing wrong? Nothing. In zone 5 it is a dud. Replace it with something better.
Not all cultivars will do well in all locations. Some just flower poorly.
Read about more hydrangea myths here: Hydrangea Myths
- Why Don’t My Hydrangeas Flower?; https://www.ces.ncsu.edu/fletcher/staff/rbir/hynonflower.html
If you like this post, please share …….
Climbing Hydrangea Care Guide: How to Grow Climbing Hydrangeas
Climbing Hydrangea Care
Climbing hydrangeas are quite slow growing, especially in a cold and always shaded position, but once established they will develop over 10 to 20 years to a height of up to 15 metres with an ultimate spread of between 4 metres and 8 metres. The ideal spot to plant them is against sound masonry walls or on very sturdy trellises or fences that are expected to last for many years. Without additional support they can sometimes come away from the frame, so to avoid disasters later on in the life of the climber when it has become top heavy, it is advisable to use training wires and plant ties form the outset, and to add more as necessary as the plant grows.
Climbing hydrangeas like to have their roots in moist (though never waterlogged) soil, and a good mulch of well rotted garden compost or other organic material every winter will help to keep moisture in the soil during warmer weather and also provide an annual boost of nutrients.
They will survive in all types of sunny and shady conditions, and many enthusiasts suggest that they have a preference for early morning sun and midday and afternoon partial or full shade. They are one of the few flowering climbers that will tolerate dense shade and keep flowering, indeed the flowers on plants grown in the shade seem to last longer than those on plants grown in the sun. Climbers grown in sunnier locations will need greater attention to soil moisture, and a regular mulch to shade and cool the base of the plant and the roots is beneficial.
Following planting, it is important that the climber is not allowed to dry out. It should be well watered in, and a suitable mulch applied to retain the moisture. The plant should be watered weekly in its first summer in the garden, or more frequently in very dry weather, until it is established.
While the climbing hydrangea is best suited to growing in a soil with moisture-retaining properties and good internal drainage, it is a relatively tough plant once established and it will survive in almost any type of garden soil, provided it is not waterlogged. Its preference is for a well-drained and light loamy or sandy soil, either neutral or slightly acidic, though it will tolerate mild alkalinity. These conditions can be promoted through the regular application of well-rotted manure, leaf mould or good garden compost.
Climbing hydrangea plants do not generally need much feeding once established, especially if they are given regular dressings of organic compost as this will improve soil fertility as well as its structure and moisture-retaining capacity. On particularly poor, light sandy soils they may benefit from an annual feed in late winter or spring with a general purpose fertiliser, but too much feeding will produce leafy growth at the expense of flower buds. It will also make the plant more susceptible to frost damage in very colder winters. Overall, it is better to err on the side of caution and to underfeed rather than overfeed.
Climbing hydrangeas do not require routine pruning, and they can generally be kept tidy and in shape simply by removing dead flower heads and trimming any unwanted shoots back to some healthy buds. If a flatter espalier that sits more tightly against the wall is desired, outward-facing side shoots can be pruned back to a pair of buds.
Always use sharp secateurs to make clean cuts and to avoid crushing the stems. Wipe the blades carefully with rubbing alcohol before trimming the plant to reduce the risk of introducing disease.
Newly planted climbing hydrangeas need time to grow adequate roots and to settle into their new position before any pruning is done. Early pruning will divert energy from root development and produce a weaker plant, so they should not be pruned in the first two years after planting.
Once it is established, it is possible to carry out a minor trim of the climber after flowering in late summer. At this time the vine can be trimmed back to maintain it within its allocated wall space, to control its height or spread, or to prevent it from growing across windows, doors or gates. For this minor pruning, no more than one third of the plant’s growth should be removed. If a more radical prune is necessary, wait until the vine is dormant to reduce stress. Cuts should be made just above leaf nodes to encourage the remaining plant to fill out. Any dead branches should also be removed.
The flowers are produced on the previous year’s growth, so if it is pruned before flowering there will be no blooms for that year.
A mature plant that has not been supported properly can sometimes get blown down in the wind, especially if it has become spindly and top-heavy. If it is damaged and cannot be easily refastened to the supporting wall, it may be better to undertake a heavy restorative pruning. Healthy vines will rejuvenate, but if possible wait until the plant is emerging from dormancy in the late winter or spring before carrying out the major pruning. Prune away the majority of the plant, leaving just three to five 1 metre high stems. It will regrow, but it should not be pruned again for at least a couple of years.
Climbing Hydrangea H. petiolaris
Commonly known as the Climbing Hydrangea, its botanical name is Hydrangea Petiolaris and it’s a fabulous showy, late spring and early summer flowering climber.
The images do not do it justice.
Climbing Hydrangea is easy to grow, too easy, a touch vigorous but not seriously so. It can be slow to get going, but once established it is fairly fast growing. It is important when first planted and establishing the shrub not to let it dry out.
A great advantage when growing Climbing Hydrangea is that it needs little or no attention. It is self clinging with aerial roots, the flowers are a creamy white and it is deciduous.
It will tolerate semi shade which makes it ideal for a north-facing wall, and a useful climbing plant for shadier areas. Although the climbing Hydrangea is most suited to growing on moist soil, it is very tough and will grow more or less anywhere.
A climbing Hydrangea can become quite large over time growing up to 25m (80ft) which means it will cover a big area, the whole of a fascia of a house in about 10-15 years if grown in ideal conditions. It does not require pruning, but if it outgrows it’s allotted space, it can be checked by pruning. The best time to prune climbing Hydrangea is after flowering in late summer, when it can be trimmed to fit the space. The flowers are produced on last year’s wood, which means if it is pruned earlier in the year before flowering, the flowers for that year will be sacrificed.
An additional bonus is that the Climbing Hydrangea is completely hardy, -15 to -10 cold winter Hardy in most places throughout the UK even in severe winters.
Climbing Hydrangea is a reliable climbing plant flowering every year with lovely, frothy, creamy white flowers and bright, almost lime, green foliage. The climbing hydrangea is suitable for growing anywhere in the UK.
Hydrangea Care Questions and Answers
My hydrangea grows beautiful green leaves, but I haven’t seen any blooms yet. How do I get my hydrangea to bloom endlessly? There are a few main reasons that you may not see blooms on your hydrangea bushes: sun exposure, over-watering and over-fertilizing. Endless Summer® hydrangeas prefer morning sun and afternoon dappled shade. If they are planted in full sun, it may be too hot and intense for the blooms to produce. Also, over-watering and over-fertilizing your plants can inhibit bloom production. Hydrangeas prefer moist, but not wet soil, and one application of fertilizer in spring or early summer. For additional planting and care tips, please . I pruned my hydrangeas back after an early frost and now I am not seeing blooms. Why is that? How to prune hydrangeas is a great question. If you pruned your hydrangeas back to the base, it will take some time for the new growth to develop and produce blooms. Be patient and look for the green growth coming up from the base of the plants. That is where your new blooms will grow from! I had several small blooms on my hydrangeas last year, so this year I have fertilized every 10 days until I saw blooms starting to develop. What else should I be doing to get big blooms? The first rule of thumb is to NOT over-fertilize your hydrangea plants. We suggest one application of granular fertilizer in spring or early summer, and then follow package instructions afterwards. If you over-fertilize, it can burn the root system of your hydrangea bushes and actually inhibit bloom production. For more tips on fertilizer and how to achieve big, beautiful blooms, please . My hydrangeas have brown dry spots on the leaves and brown petals on the bloom. What do I need to do to make the hydrangeas healthier? If the spot is round and brown with a red to purple ring, you likely have Anthracnose. Remove the affected leaves and dispose away from your plants. Treat with a fungicide and repeat as necessary. If the margins of the leaves fade from green to grey and then turn brown, the plants were dry for too long. If the petals of the flowers turn brown at the tip, not enough water was applied. Both the leaves and the flowers will show lack of water very quickly. I planted my hydrangeas in a location with at least 6 hours of full sun and partial afternoon shade. I read online that hydrangeas prefer that I water them heavily once a week instead of a little water every day. Now my hydrangea bushes are turning brown with no blooms. What am I doing wrong? Depending on where in the United States you live will determine how much sun your hydrangeas can handle. If you are in a northern state (Zones 4 – 5b), your hydrangeas can handle up to 6 hours of sun in the morning, but as you get further south you should allow for more shade on your plants. In the southern-most regions (Zones 8 – 9), we recommend a maximum of 2 hours of morning sun. Too much sun exposure can cause your hydrangea shrubs to burn on its leaves and blooms. Also, be sure to put your fingers in the soil to see if it needs watering. We do recommend a soak versus light watering each day, but you should be sure that the soil is always moist – not wet – by sticking your fingers in the dirt. If it is dry, give it a good soaking. If it is wet, do not add water. For more information on where to plant and how to water, please . Do these hydrangea plants survive in containers? Our garden gets really hot, so I think a container would be a better option. Do I follow the same care instructions (watering, fertilizing, etc.) as I would in the garden? Absolutely! Hydrangea shrubs are perfect as potted plants and give you the ability to move the hydrangeas to different locations and create a focal point in your living space. The care instructions are mainly the same, with a few notable differences. For a complete look at container care, . What type of fertilizer do you recommend? I know that hydrangea bushes do best with certain kinds of fertilizer because of their big blooms, but am not sure what to buy! We recommend a granular, slow-release fertilizer with a NPK ratio of 10-30-10. If you cannot find that specific ratio, ask your local nursery for a fertilizer with a high concentration of phosphorus, as that encourages the bloom growth. For more information, please I bought these plants because I wanted big, beautiful blue hydrangea bush in my garden. I got big blooms, but they are PINK! What did I do wrong? The pH level of your soil determines hydrangea colors. If you have a pink hydrangea and you want a blue hydrangea, no problem! Pink blooms develop in alkaline soil, so certain amendments need to be made to lower the pH and create an acidic soil situation. We suggest Color Me Blue soil sulfur to encourage blue bloom production. This is safe, organic and all-natural. There are also other natural remedies to changing hydrangea colors. To encourage blue blooms in alkaline soils, add aluminum sulfate, composted oak leaves, pine needles or coffee grounds. There are more tips, including how to change from blue blooms to pink hydrangea, . I planted my Endless Summer hydrangea in an area that is far too sunny and hot, so I’d like to transplant them to a more shaded area. What is the best time of year to do this, and are there any other tips I should know? If you are transplanting your hydrangea bushes, we recommend doing so while it is dormant.That means transplanting your hydrangea shrubs in late fall, after the first frost, or in early spring before it has woken up for the summer. I live in an area that gets a lot of snow during the winter. Should I prune Endless Summer Hydrangeas back like I do with my other hydrangea bushes? What else should I do to protect them from the freezing winter months? The great thing about Endless Summer® hydrangeas is that you don’t need to prune them back to the base like other hydrangeas. Since they bloom on previous years’ growth AND the new season’s growth, you can leave them all winter long to achieve double the blooms next spring. Do NOT prune the hydrangea back in fall. Leaving the fall blooms on your plants over the winter provides winter interest, and ensures you aren’t removing buds that will become flowers in the spring and summer. Leaves, wood mulch and/or straw are good options to insulate your plants. Mound the mulch or leaves around your plants at least 12” high to protect the flower buds that will bloom early next year. For more Overwintering tips, please . If your hydrangeas are planted in containers, please . Where can I buy Endless Summer hydrangea? To find the closest nursery that sells Endless Summer® hydrangeas, please enter your zip code in the “Find A Retailer” box above.
How to Grow a Climbing Hydrangea
The hydrangea is the undisputed Queen of the Southern Garden. Whether you grow, a big leaf, panicle, smooth, or oakleaf variety, a well-tended hydrangea will give you lots and lots of gorgeous blooms throughout the season. Looking across a yard at a bank of hydrangea bushes in full bloom is certainly a site to behold, but consider looking upward to the climbing hydrangea, a flowering vine that produces fragrant, lace-cap white flower clusters. Using the suckers on the branches, a climbing hydrangea will scale walls and other structures, sometimes reaching 50 feet tall or more at maturity.
Where and How to Grow
Climbing hydrangea vines can scale tree trunks, sturdy trellises, arbors, and fences. The vines become large and heavy over time so be sure that the host structure can support the weight of the vines and the structure is not something (like the side of a clapboard house) that may rot or need replacing or repainting. The plants can also be pruned to maintain a shrub-like form. Climbing hydrangea can also be used as ground covers, taking root where the suckers make contact with the ground and filling in the area. Some gardeners like to use a climbing hydrangea as ground cover in their moon gardens. Here is one more reason to love climbing hydrangeas: they are salt-tolerant plants and are very popular in seaside communities. The vines commonly don’t bloom until they are three to five years old so just be patient.
Climbing hydrangea is one of the few hardy flowering vinesthat tolerate shade. In hot climates, choose a location where the plant will get some partial shade. In the cooler regions of the South, the vine will usually do well in more sunny areas, if adequately watered. Climbing hydrangeas that do get more sun tend to bloom better.
Soil, Feed, and Water
Climbing hydrangea needs a rich, moist, well-drained soil. If your soil needs improvement, mix in a generous amount of compost before planting. Apply a 3-inch layer of mulch to help retain water in the ground around the root zone and reduce weeds. Fertilize this plant in the spring before the leaves begin to bud. Granular fertilizer with a high phosphorous count will create beautiful blooms. Fertilize again after the flowers have bloomed in the summer. As with other hydrangea plants, this species likes constantly moist soil. Place it where it will get watered about 1 inch weekly, or even more often in hot weather. Interesting side note about the word hydrangea: the Greek root hydrrefers to water, and angeon comes from the Greek for “vessel.”
Temperature and Humidity
This plant is hardy in USDA plant zones 5 through 7, does well in temperate climates but may wilt in hot, humid conditions. It can be damaged by sunburn and prefers daytime temperatures around 70 degrees Fahrenheit and night temperatures around 60 degrees. It will set buds only if there are six weeks of temperatures below 65 degrees. A sudden frost can damage the buds and you may not see flowers the next year.
WATCH: Essential Southern Plant: Hydrangea
As stated above, newly planted climbing hydrangea vines are slow to grow and slow to bloom. Once the plants are established, however, climbing hydrangea tend to be vigorous growers and, depending on where they are growing, may need pruning in summer to keep them under control, if desired.