Hydrangea Not Blooming? (6 Solutions That Actually Work)


Why is my hydrangea not blooming

This is a problem I had when I first started gardening. I had a beautiful big hydrangea that did not seem to bloom! This set me off on a mission to discover all the secrets and insider tips on how to promote flowering, so I did my research and even spoke to a lot of specialist growers that I met in my day job working at a garden nursery.

In this article, I distill have everything I have learned so you can identify the reason why hydrangea is not flowering and how to fix it…

Pruning at the wrong time of year and Winter damage to the flower buds are the most common reasons for hydrangeas not blooming. Hydrangeas flower buds develop on old wood. Pruning last year’s growth removes the developing flower buds and stops your hydrangeas from blooming.

As there are a few reasons I have encountered for hydrangeas not flowering, I have listed the most common reasons here:

  1. Pruning hydrangeas in the Spring removes last year’s growth and the developing flower buds.
  2. Late Spring frosts can damage the emerging blooms in Spring and prevent flowering.
  3. Too much nitrogen in the soil causes lots of foliage to grow but with fewer flowers.
  4. Hydrangeas require partial sun or dappled light to flower, and too much shade can prevent flowering.
  5. Hydrangea is not yet mature enough for flowering.
  6. Drought stress in Fall and Spring can harm the development of flower buds.

Keep reading to learn why your hydrangea is not blooming and to solve the problem…

1. Pruning Can Prevent Flowering- Hydrangeas Bloom on Old Wood

This is the mistake that I personally made when first trying to get my hydrangea to flower!

Hydrangeas only flower from shoots that come from last year’s growth. If you prune hydrangea too heavily or at the wrong time of year then you cut back into the growth from which the flowers emerge and prevent the hydrangea from blooming until the following year.

We need to remember that our hydrangeas do not need regular annual pruning like other shrubs (like roses) do and often flower best when you leave the plant alone to bloom.

If you have pruned your hydrangea back significantly,, it tends to grow lots of lush green foliage in the Spring without any flowers, like mine did!

How to Solve it:

I love hydrangeas as I discovered they are very forgiving. Hydrangeas are very resilient once established, and a heavy pruning only tends to delay blooms until the following year.

When pruning hydrangeas, what I now do is focus on cutting back any straggly stems or dying back to the base to encourage new growth that can support more flowers. I must caution against reducing the shape of your hydrangea, as pruning hydrangeas should generally be limited to deadheading.

It is best practice to cut away any dead growth back and spent flower heads to new healthy growth or the next flower buds in the Spring as this encourages more airflow and allows more light on the developing blooms.

I must emphasize that heavy annual pruning is unnecessary and will likely prevent your hydrangea from flowering as hydrangeas flower from old wood.

Pro tip: If pruning your hydrangea is necessary because it is too large for your garden, then I recommend cutting back your hydrangea straight after flowering. This can give the hydrangea enough time for new growth to develop and next year’s mature growth, which can support flowers the following year.

For a great visual guide on pruning and deadheading to encourage flowers, watch this YouTube video:

2. Winter Damage to Flower Buds

Hydrangeas often do not bloom because of frost damage to the flower buds in spring. The emerging flower buds are particularly sensitive to a sudden drop in temperature, and late Spring frosts damage the buds and prevent the hydrangea from blooming.

While hydrangeas are hardy in freezing temperatures during Winter, the new emerging growth is vulnerable in the Spring. If the hydrangea flower buds and new growth appear brown or black, this is the clearest sign of frost damage.

I find this one so frustrating because I live in a climate where I occasionally get caught off guard on some years.

Hydrangeas are adapted to living in woodlands where the shelter of the forest canopy provides some protection from the effects of frost and adverse weather conditions. Therefore, always avoid planting hydrangeas in open and windy areas, which can decimate tender new growth.

How to Solve it:

Pro tip: A good way to protect the emerging flower buds is to resist the urge to deadhead and actually leave the old flower heads from the previous year on the plant.The old flower heads act as an effective form of protection against frost and insulate the new buds from cold temperatures similar to horticultural fleece.

This increases the chance of the buds surviving any late frost to ensure your hydrangea flowers well.

For this year’s flowers, we need to trim back any frost-damaged growth with pruners, as it does not revive.

By trimming back the damaged growth you allow more light to flower buds that have formed further down the stem which are more likely to survive a frost as they are often afforded some protection from the foliage.

The damage to hydrangeas tends to be limited to the outer most growth after a frost so with some patience the buds can often still flower that are further down the stems rather then at the outer most points of the hydrangea and you should still see some blooms later in the Summer.

Pro tip: If I know there is a late frost forecast, what I sometimes do is wrap my entire hydrangea up in horticultural fleece when provides enough insulation to my hydrangea’s developing flower buds to prevent frost damage and my hydrangea flowers great in the Spring!

(Read my article on how to revive a dying hydrangea).

3. Too Much Nitrogen Fertilizer (Reduce Fertilizer use)

Have you applied too much fertilizer for your hydrangea to flower?

Applying fertilizer too often or in too high a concentration can cause the hydrangea to grow lots of foliage at the expense of flowers. Hydrangeas only require a well-balanced fertilizer applied at the start of Spring to encourage flowers.

All plants require Nitrogen, Phosphorous, and Potassium (NPK) to grow and flower, but if there is a high amount of nitrogen in the soil then this causes the stems, leaves, and flower heads of the hydrangea to become sappy, weak, and droop with far fewer flowers on display.

Sappy weak growth from using too much fertilizer also leaves your hydrangea at greater risk of pests and diseases.

You must get the right balance of fertilizer for hydrangea to display flowers.

Remember that we can kill our plants with kindness!

Solution…

Personally, I recommend using a well-balanced fertilizer such as miracle-gro all-purpose granular fertilizer for hydrangeas, which contains all the nutrients a hydrangea requires for growth and blooming at the right concentration.

The granular formulation releases the nutrients slowly, helping to mitigate any risk from using too much fertilizer or applying it in too high a concentration, which is a common problem with other types of fertilizer.

Miracle-gro all purpose fertilizer helps to mitigate the risk of using fertilizer too often or in too high concentration which can reduce hydrangea blooms.
I personally use this Miracle-gro all-purpose fertilizer as it helps mitigate the risk of using fertilizer too often or in a concentration that is too high, which can reduce hydrangea blooms.

If your hydrangea has lots of sappy foliage growth with few flowers, then scale back the use of your current fertilizer and monitor for insect infestations or disease.

If established, hydrangeas are usually very hardy plants that withstand a lot of mistreatment. Therefore, it is likely that the hydrangea can recover and display flowers the following year if you use the right sort of fertilizer and follow the manufacturer’s instructions.

Once the fertilizer has been applied, you cannot do much to promote blooms in the meantime, so I must caution that some patience is required.

It is important to note that lawn fertilizer can often dilute in heavy rainfall and run off into garden borders where your hydrangea and other plants are planted.

Lawn fertilizer is particularly high in nitrogen, which is often a cause of plants in the surrounding borders not flowering if there is significant runoff after rainfall. This is a problem I have seen several times.

(Too much fertilizer often causes hydrangeas to have a drooping appearance. However, there can be a few different reasons for this. Please read my article, why is my hydrangea drooping for the solution).

4. Not Enough Sunlight for Flowering

In my experience, hydrangeas flower best in the morning sun, followed by afternoon shade or dappled light. If they are in full shade all day, they grow lots of foliage but without any flowers. Sunlight helps to stimulate more flowers, and afternoon shade protects the hydrangea from leaf scorch.

In my garden, my hydrangeas flower best in 4 to 6 hours of morning sun or dappled light under a tree canopy to give them the energy for flowering.

How to Solve it:

Shading the hydrangea in the afternoon is best, as the intense sunlight and high temperatures often cause drought stress and can scorch the leaves. So, either find a location with morning sun and afternoon shade or an area of dappled light under a tree canopy that allows some light throughout the day for the optimal balance of sun.

If your hydrangea is not blooming, I would consider whether the surrounding tree canopy is casting too much shade on it, depriving it of the sun required for blooming.

In this case, you may consider cutting back some of the overhanging branches which help to create the dappled light conditions for the balance of sun and shade to help stimulate blooms and protect the delicate leaves from scorch.

If cutting back tree limbs or creating more light is impractical, consider whether you could transplant the hydrangea to a sunnier location in the garden.

The best time for transplanting hydrangeas is in the Fall when the soil is still warm enough for the roots to establish and hydrangeas do not have to contend with the stress of high temperatures, blazing sunshine, and transplant shock in Summer.

5. Hydrangea, not Mature Enough To Flower

Good things come to those who wait…especially hydrangea blooms!

I have learned that hydrangeas often do not flower in the first year after planting as they invest their energy into developing the root system and adjusting to their new conditions rather than displaying flowers. Hydrangeas tend to bloom more the year after planting, or once they have matured for a few years in the soil.

When you purchase a hydrangea from a garden center or nursery, it is likely to have been cultivated in a greenhouse with optimal conditions (such as controlled temperature, light, soil, fertilizer, and airflow) before sale.

This means that the hydrangea has adapted to growing in a very specific and controlled set of conditions that are in contrast to those in your garden.

Therefore, hydrangeas can experience transplant shock after planting as they adjust to their new conditions.

This transplant shock can prevent your hydrangea from blooming in the first year after planting. The hydrangea is more likely to redirect its energy from displaying flowers to establishing its root system in the new garden soil.

It is important to consider the size and maturity of your plant as smaller, young plants also invest their energy into growth, particularly of the roots as immediate survival is the main priority rather the displaying flowers.

How to Solve it:

When the hydrangea has had time to adapt to its new surroundings, and as long as the hydrangea has good conditions for growing (partial sun, moist, yet well-draining soil, etc), then I can assure you hydrangea should establish after a year or so and grow into a larger more mature plant, then it can afford to display flowers the following year.

It is important to note that larger hydrangeas are more likely to flower in their first year than smaller plants.

Wait a year or so for the plant to mature, and ensure the hydrangea has all the conditions it requires to thrive then it should bloom well the following year.

(Read my article, why are my hydrangea flowers turning green?)

6. Not Enough Water While the Flower Buds Develop

Hydrangeas require well-draining yet consistently moist soil, so if the soil around the roots dries out, this causes drought stress, which can prevent the development of flower buds and ultimately cause your hydrangea to not bloom.

One year, we had a very dry Spring, which seriously impacted the number of flowers on my hydrangea.

As we discussed previously, hydrangeas are naturally woodland plants that grow in soil composed of lots of organic material, which holds onto moisture and has a porous, friable stricture that allows excess water to drain away rather than become waterlogged around the roots.

The leaves of the woodland floor also act as natural mulch for the hydrangea, helping to conserve moisture around the roots and prevent the soil from drying out.

If your hydrangea is in a smaller pot, in sandy soil that drains too quickly, or where there has been a lack of rainfall, particularly in the Spring when the flower buds are developing, it will have poor growth and fewer flowers.

I have had much more success planting my hydrangeas in larger pots or containers. Larger pots have a greater soil capacity and, therefore, can hold more moisture than smaller pots, which dry out too quickly for hydrangeas to tolerate.

What I find really works is planting hydrangeas in garden boarders that have been prepared with lots of organic matter (compost, leaf mold, or well-rotted manure) around the planting area to recreate the optimal soil conditions and the ideal balance of drainage and consistent moisture, that hydrangeas require for flowering.

If there are drought-like conditions, then give your hydrangea a really generous soak, preferably with a soaker hose, so that the surrounding soil is evenly moist.

As we talked about, I love to apply a 2-inch layer of mulch (leaf mold, compost, or well-rotted manure all work great) to the surface of the soil surrounding my hydrangea to help conserve the moisture, improve the soil structure, and prevent the sun from shining directly on the soil which can dry out the soil and heat up the roots which cause the hydrangea stress.

Water your hydrangea as often as required to keep the soil evenly moist. Water your hydrangea generously, as this encourages good root development, which increases the hydrangea’s resistance to dry conditions.

I make sure my hydrangea is well watered in early Spring to prevent this from happening again, but to be honest, if my hydrangea is in a garden border, as long as I have mulched it, I usually don’t need to water it again for the rest of the year, and it always blooms reliably.

With good, evenly moist soil that has been amended with organic matter, partial sunlight, and fertile soil, the hydrangea has the required conditions to display flowers the following year.

(Read my article, why is my hydrangea wilting?)

Key Takeaways:

  • Pruning last year’s growth from a hydrangea in the Spring removes the developing flower buds and is the most common reason for hydrangeas not blooming. Hydrangeas flower on old wood and bloom best when they are not pruned annually.
  • Emerging hydrangea flower buds are very sensitive to cold temperatures, and a late Spring frost or excessive cold winds can cause the new growth to turn brown and stop your hydrangea from flowering.
  • Hydrangeas do not flower if there is too much nitrogen in the soil due to using a fertilizer too often or in a concentration that is too high. Hydrangeas produce lots of lush green foliage growth with few flowers with too much nitrogen in the soil.
  • Hydrangeas grow naturally in woodland in the dappled light of a tree canopy. If the hydrangea is in full shade, it tends not to flower but still grows plentiful foliage. Hydrangeas flower most often in the morning sun, followed by afternoon shade or in areas of the garden with filtered light.
  • Hydrangeas only flower to their full potential when they are mature plants that have been established for several years. If the hydrangea is small or has been recently transplanted, it redirects energy to establishing its root system and does not display flowers for a year or so.
  • The hydrangea’s developing flower buds require consistently moist soil to form properly. If there is a period of drought or dry soil in the Spring or Fall when the buds are developing, the hydrangeas will not display flowers until the following year, when the soil conditions are favorably moist.

One thought on “Hydrangea Not Blooming? (6 Solutions That Actually Work)

  1. hello i have had a hydrange for 5 years. every year it has beautiful green leaves but never blooms. what should i do to get blooms. thank you

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