What month do hydrangeas bloom?
When to prune hydrangeas for best bloom
Hydrangeas are one of the most popular blooming woody shrubs in Minnesota landscapes and, as you’d expect, people often ask how and when to prune these beloved shrubs.
Hydrangea paniculata, panicle hydrangea
Prune back stems to just above a fat bud — called a heading cut — in fall, late winter or spring. These plants have conical-shaped flower heads. I recommend leaving the dry, tan flower heads on the plant to provide some winter interest in your landscape, so I wait to prune these until late winter or spring. Some favorite panicle hydrangeas:
- Quick Fire® (H. paniculata ‘Bulk’ PP16, 812)
- Limelight (H. paniculata ‘Limelight’)
- First Editions® Berry White® (H. paniculata ‘Renba’ PP28, 509)
Hydrangea macrophylla, big leaf hydrangea
These plants produce buds in late summer to early fall (August-September) that will form next year’s flowers. So prune these shrubs after they finish blooming before August (again, make a heading cut).
An exception is the Endless Summer® The Original Bigleaf Hydrangea (H. macrophylla ‘Bailmer’ PP15,298) and other cultivars in the Endless Summer series from Bailey Nurseries such as Blushing Bride, BloomStruck® , Summer Crush®, and Twist ‘n’ Shout®.
The H. macrophylla bloom on last year’s wood and new wood that grows this year. So it will bloom whether you prune it or not. Protect H. macrophylla in winter from rabbit browsing on the stems with a large, 4-foot tall ring of hardware cloth.
The Endless Summer hydrangea made a huge splash on the Minnesota landscape plant scene because of its pink to blue color flowers (achievable with proper soil amendment) and because it blooms on old and new wood.
Hydrangea arborescens, smooth hydrangea
Let these plants grow a season or two before doing any serious «hard» pruning. Once the shrub is established and has a couple of growing seasons under its belt, prune these hydrangeas in the spring down to the ground, or not at all if you want a larger shrub. Flower buds will grow on this season’s growth or new wood.
Some favorite smooth hydrangeas:
- Invincibelle Mini Mauvette® (H. arborescens ‘NCHA7’ PP30,358)
- Incrediball® (H. arborescens ‘Abetwo’ PP20571)
- Annabelle (H. arborescens ‘Annabelle’)
Hydrangea petolaris or climbing hydrangea
This tough, gnarly vine needs little to no pruning ever, except for removing any dead wood that develops.
Plant this vine in full sun on a solid trellis or fence where you want a long-living, dense screen. It is a dickens to get rid of once it gets established.
(6 Reasons) Why Your Hydrangea Isn’t Flowering
Hydrangeas of all cultivars should bloom as early as Spring or mid Summer through till late Summer with each flower lasting for several weeks. The reasons for hydrangeas not flowering are too much fertilizer, lack of sun, transplant shock, moisture stress, frost damage on developing flower buds and because of hard pruning the old wood which supports this seasons new hydrangea blooms. Keep reading for more information on why your hydrangea isn’t flowering and how to ensure your hydrangea flowers abundantly next year…
1. Too Much Fertilizer Causes Fewer Flowers
- Symptoms: Hydrangea has bushy green foliage with few or no flowers.
- Causes: Excess fertilizer applications causes conditions that are too high in Nitrogen for hydrangea to flower.
One of the most common reasons for hydrangeas to not flower as much as they should is because of high strength fertilizer or too many applications of nitrogen based fertilizer.
Excess nitrogen promotes foliage growth at the expense of flowers which is why you have to be careful when applying fertilizer to hydrangeas.
With good soil preparation prior to planting (amend the planting area with lots of compost) and regular applications of mulch, most established hydrangeas do not require any fertilizer and bloom exuberantly throughout the Summer.
However if you have a potted hydrangea or your soil does not retain much nutrients then an application of fertilizer can be beneficial for the healthy and flowering of your hydrangea.
How to Solve it:
Scale back any applications of fertilizer as nitrogen can encourage abundant soft leaf growth that is more vulnerable to frost damage as well as fewer flowers.
If your soil is poor or your hydrangea is potted then an application of a half strength balanced fertilizer applied once in the Spring and then again in the Summer around July is all the hydrangea requires for spectacular blooms.
Choose a general fertilizer that has a ratio of equal parts Nitrogen Phosphorous and Potassium (NPK) to ensure all the nutrients a hydrangea requires without over indulging the plant with nitrogen.
For established hydrangeas in good soil, the best way to ensure blooms is with an application of mulch to preserve moisture, and slowly add nutrients to the soil and the hydrangea should display spectacular blooms without requiring any additional fertilizer applications.
2. Not Enough Light for Flowering
- Symptoms: Poor spindly or slow growth with few blooms.
- Causes: Shade without any indirect bright light or sun.
Too much shade can also impact the blooms of a hydrangea.
Whilst hydrangeas can flower well in the shade, most hydrangeas flower more extravagantly in the dappled light under a tree canopy or in partial sun as this replicates their natural growing conditions.
Consistent shade without any bright light or full sun, can cause spindly growth of both stems and foliage with few flowers.
How to solve it:
The only way of fixing the problem of low light is to:
- Transplant the hydrangea to a sunnier location.
- Cut back any over hanging tree limbs that may be over grown and cast too much shade over the hydrangea.
Full sun often can often scorch the leaves of hydrangea (particularly in hot climates) so it is important to find a good balance of shade and sunlight with either some dappled light or exclusively morning sun to ensure hydrangeas flower to their full potential without suffering in the sun.
The species Hydrangea paniculata is the hardiest and most versatile hydrangea, adapting well to full sun as well as shade.
Once you have transplanted your hydrangea or cut back overhanging plants the hydrangea should display more blooms the following year.
Here is a YouTube video for how to successfully transplant hydrangeas:
3. Pruning at the Wrong Time and Pruning too Hard Prevents Blooms
- Symptoms: Hydrangea that has been pruned well back the previous year displaying no flowers.
- Causes: Pruning back too hard cuts into the wood from which flowers are produced.
Hydrangeas flower from mid Summer to late Summer (June/July until late August) on shoots that emerge from last years growth.
Hydrangeas do not necessarily require an annual pruning in the same way roses do and still display lots of flowers, however consistent light pruning is best practice to stimulate blooms.
When and How to Prune for Flowers:
- The best time to prune hydrangeas is in the Spring. To increase the chance of flowering, leave the faded flowers from the previous year on the hydrangea as they provide the developing flower buds with protection from frost over winter, although in mild climates where frost damage is less of a threat hydrangeas can be pruned at the end of Winter.
- Hydrangeas do not respond well to hard pruning. Whilst hard pruning is not necessarily detrimental to the health of your hydrangea, it can cause it not to display flowers for up to two years. Hard pruned hydrangeas that are cut well back tend to grow back with lots of new shoots and green foliage but with no flowers.
- Cut back the previous years spent flowers back to the first healthy pair of buds on the stem in the Spring.
- Whilst faded flowers may not look tidy over Winter, it is often a compromise that you have to make to ensure the best chance of flowering the following spring and you may be rewarded with record blooms.
- If there is any old wood that does not appear to be very productive in terms of new growth or perhaps dying back then selectively cut back these stems as low to the base of the hydrangeas as you can as this encourages new growth to replace it that can host more flowers.
Pruning hydrangeas for optimal flower displays is easy and the plant is forgiving compared to other plants so do not worry if you make a mistake as the hydrangea should grow back well the following year.
Here is a helpful YouTube video for a visual guide to pruning hydrangeas:
4. Winter Frost Damage
Frost damage, particularly late frosts in the early Spring can potentially damage the developing flower buds which then turn brown.
This can compromise the flowering of your hydrangea and is one of the reasons hydrangeas prefer some shelter under trees, rather then exposed and windy locations.
Frost damaging developing new tender buds is one of the key reasons for leaving the old flower heads on hydrangeas over Winter as whilst the spent flower head does not necessarily look neat and tidy over Winter it does function as effective protection for the developing buds.
In the case of damage flower buds due to frost, use your secateurs to cut back frost damaged growth to the next buds as the buds on the outermost part of the plant are most exposed and therefore likely to be damaged whilst flower buds further down the stem are often preserved.
5. Transplant Shock or Young Plants Can Affect Flowerings
If you have just moved a hydrangea or recently planted a young plant from a garden centre then it can take a year to become established before it displays flowers, although some can flowers in the first year with no problem.
This is particularly prevalent for plants that have been cultivated in optimal controlled conditions in the nursery and then they face a contrast in temperature light levels, soil and moisture when planted in your garden.
Young or recently hydrangea plants may take some time to establish in their new home before the flowers as their energy directed to producing new roots and foliage and adjusting to the new conditions.
However as long as hydrangeas are in the following conditions they can establish and to their new environment and start to display flowers freely after the following year:
- Planted in partial shade.
- Planted in soil that has been amended with lots of compost.
- Watered frequently throughout the first year.
6. Moisture Stress
Hydrangeas require the soil to be consistently moist yet free draining as the roots do not tolerate saturated ground.
For established hydrangeas if the soil has been well prepared before planting (amended with lots of organic matter) and regular applications of mulch in the Spring and there is enough shade to conserve moisture, then hydrangeas often do not require any additional watering in temperate climates.
However in hot climates or for hydrangeas that are planted in sandy/stony soils hydrangeas can suffer drought with drooping leaves.
Drought can affect the formation of buds and limit the time the flowers last on your hydrangea.
In times of drought water the hydrangea as frequently as required to keep the soil moist to a fingers depth and apply a mulch of compost, leaf mould or well rotted manure to further conserve soil moisture and the hydrangea should have all the resources it requires to stay in flower.
Equally, slow draining boggy soils can cause problems such as root rot which not only prevents blooms but can kill the plant.
If your garden soil is naturally boggy and slow draining then it is far easier to plant hydrangeas in a large pot with plenty of compost to hold moisture yet provide better drainage to avoid root rot.
- Hydrangeas do not bloom due to lack of sun, too much fertilizer, frost damage on developing flower buds and because of hard pruning of last years wood which supports this years hydrangea flowers.
- Hydrangeas recently planted often bloom more abundantly when the become established after the first year.
- Moisture stress due to drought or boggy soils can prevent hydrangeas from flowering.
- Hydrangeas prefer morning sun or dappled light, good quality evenly moist soil amended with compost and careful pruning down to the first buds in Spring to flower to their full potential.
When Do Hydrangeas Bloom (Key Factors + Plant Care Tips)
Hydrangea plants are popular for their elegant and colorful flower clusters.
But when do hydrangeas bloom?
A hydrangea bloom depends on several factors like:
- Hydrangea Types and Seasons
- Planting time
We’ll explore these factors and other essential hydrangea care tips.
Also Check Out
- Explore key characteristics of the Perfect Hydrangea Soil and important plant care tips.
- Discover the Differences Between Indoor vs Outdoor Potting Soil .
When Do Hydrangeas Bloom: 4 Influential Factors
Four factors mainly affect hydrangea bloom time:
1. Hydrangea Types and Seasons
The blooming periods of popular hydrangea varieties include:
- Hydrangea petiolaris (climbing hydrangea)
- Hydrangea quercifolia (oakleaf hydrangea)
- Hydrangea serrata (mountain hydrangea)
- Hydrangea macrophylla (bigleaf and mophead hydrangea)
- Hydrangea arborescens (annabelle and smooth hydrangea)
- Hydrangea marcophylla normalis (lacecap hydrangea)
- Hydrangea paniculata (panicle hydrangea)
- Planting hydrangeas between fall and early spring gives the shrub time to form a healthy root system.
- To avoid heat stress, plant hydrangeas at cooler times, like early morning or late afternoon. Planting at the wrong time can cause scorched leaves and buds, resulting in delayed flowers until the following year.
- Protect your hydrangea from harsh winds and full sun by choosing a well-sheltered location (preferably the north or south of your home).
- Old wood hydrangeas: Certain hydrangeas bloom on old wood (last year’s growth). Avoid pruning these hydrangeas around winter, as they may produce flower buds that bloom the next year.
Old wood hydrangeas include:
- Mophead hydrangea
- Lacecap hydrangea
- Bigleaf hydrangea (excluding cultivars like Endless Summer)
- Climbing hydrangea
- Oakleaf hydrangea
- Panicle hydrangea
- Smooth hydrangea (known for its large, white flower head)
- Little lime hydrangea
- Limelight hydrangea
- Endless summer hydrangea
- Let’s dance starlight hydrangea
- Everlasting hydrangea
- Choose the right soil: Opt for nutrient-rich, well-draining, and moist soil, like Rosy’s hydrangea soil . It’s Earth Positive, well-draining, and nutrient-rich — perfect for all types of hydrangeas.
- Provide adequate light: Place hydrangeas in shaded areas where they can get plenty of early morning sun but away from harsh winds and direct sunlight.
- Water appropriately: Water your hydrangeas when the top 2-3 inches of soil is dry ( preferably early morning or evening to avoid quick evaporation).
- Improve soil fertility: Consider using organic fertilizer (like compost, manure, or worm castings) once or twice in the summer.
- Keep pests and diseases away: Use an organic insecticide/fungicidal spray to eliminate pests, but keep the leaves dry to prevent fungal diseases.
- Hydrangeas absorb aluminum at low pH levels (acidic soil) to produce beautiful blue flower clusters.
- They bloom vibrant pink flowers at high pH levels (alkaline soil.)
2. Ideal Temperatures for Hydrangeas to Bloom
Different hydrangea varieties flower at different temperatures. But most of them prefer a moderate climate.
Keep your hydrangea away from winter frostbite or summer sunburn, whether a bigleaf hydrangea or mountain hydrangea.
3. When and Where to Plant Hydrangeas
Want to help your hydrangeas bloom?
Follow these pro tips when planting hydrangeas:
4. How You Prune Hydrangea
Pruning hydrangeas do more than shape your plant — it increases the flowering branches for future flower clusters.
How to go about pruning hydrangeas?
Fun fact : Endless summer was the first bigleaf hydrangea to bloom on both old and new wood, becoming the first reblooming hydrangea.
Important Hydrangea Care Tips
Use these home gardening tips to help your hydrangea shrub bloom
4 FAQs on Hydrangeas
Have more questions about blooming and growing hydrangeas?
1. Does a Hydrangea Flower Every Year?
Hydrangeas bloom seasonally and typically start to bud around mid-summer or late summer.
However, a newly planted hydrangea may take 2-3 years to bloom.
2. How Long Does a Hydrangea Bloom Last?
The hydrangea flower clusters can last up to 2 months, depending on the cultivar, climate , and how well you take care of them.
3. How Do You Control the Hydrangea Flower Color?
You can control the flower color of some hydrangea (like bigleaf hydrangea and mophead hydrangea) based on the soil pH levels.
Here’s how to get blue or pink flowers:
4. How Do You Keep Hydrangea Blooms from Wilting?
Hydrangeas don’t like extreme conditions.
Avoid overwatering or underwatering, and place the plant in areas with partial shade.
Enjoy Your Hydrangea’s Best Blooms
A variety of hydrangea species bloom from early summer through early fall, depending on the factors we covered above.
Follow our tips to provide the right flowering conditions for your hydrangeas.
And if you’re looking for the perfect soil, try Rosy’s hydrangea soil for optimal care. Our Earth-Positive soil optimizes drainage and boosts aeration, helping your hydrangeas thrive and produce stunning blooms.