I love hydrangeas, so I share your dismay if yours is turning brown!
I have cared for hundreds of hydrangea plants as both a landscape gardener and in my day job working in a garden nursery, and I have gained lots of knowledge about how to care for hydrangeas and how to identify why the leaves or flowers are turning brown.
Most often, I see hydrangea leaves and flowers turn brown because the leaves are losing more moisture than the roots can draw up. Excess wind saps moisture away from the leaves, causing them to turn brown and curl up. Lack of moisture around the roots causes leaves and flowers to turn brown.
However, I have encountered several reasons why hydrangeas can turn brown, so I listed the most common reasons in the order of which I see most frequently:
- Hydrangea requires the soil to be consistently moist. Dry soil causes the leaves and flowers to turn brown and wilt.
- Excess wind saps moisture from leaves more quickly than the roots can draw up moisture, causing the leaves to turn brown and curl up.
- Potted hydrangea leaves and flowers turn brown if the pot is too small and dries out too quickly.
- Too much sun can scorch hydrangea leaves and flowers turning them brown and crispy in appearance.
- Fertilizer burn causes the edges of hydrangea leaves to turn brown.
- A cold snap in Spring can cause the emerging leaves and flower buds to turn brown and mushy.
- Leaf spot fungus from overhead watering can cause brown spots on hydrangea leaves.
Please keep reading for to pinpoint why your hydrangea is turning brown and for my steps on how to fix it…
Table of Contents
Why are My Hydrangea Leaves and Flowers Turning Brown and Wilting?
A very common reasons I see hydrangea leaves and flowers turn brown because the hydrangea is losing more water from the leaves than it can draw up at the roots. If the soil around the roots is not consistently moist the hydrangea leaves and flowers turn brown and wilt as a sign of stress.
We should remember that hydrangeas grow in woodlands naturally where they are sheltered from wind, sun and have access to lots of moisture.
Too much wind can sap moisture from the large surface area of the leaves that even if the soil is moist around the roots. The hydrangea leaves and flowers can still turn brown and curl up as the roots cannot draw up and replace the water loss quick enough from the leaves.
Your hydrangeas require soil that retains lots of moisture around the roots to prevent them from turning brown.
A classic problem that I used to come across when I worked as a gardener is that the hydrangea is planted in dry, sandy, or stony soils, as water drains too quickly for the hydrangea’s roots to draw up the moisture it needs, which can be the cause of your hydrangea leaves turning brown and wilting.
There is no universal specific guide on watering for hydrangeas that I can give you, as it depends on climate, weather, and factors such as the maturity of the hydrangea plant but hydrangeas should be watered (with a thorough watering) as often as required so that the soil is moist.
At the hottest times of the year, it may be necessary to water your hydrangea nearly every day if your hydrangea is planted in a pot.
The Solution…
To revive hydrangeas with brown leaves and flowers, we need to recreate the conditions of the hydrangea’s native environment by planting hydrangeas in moisture soil, watering the hydrangea as often as required to keep the soil moist and sheltering the hydrangea from wind which saps moisture.
- Ideally, your hydrangeas should be planted or transplanted in soil that has been amended with organic matter (compost, leaf mold, or well-rotted manure) to a depth of 18 inches, which is deep enough to accommodate the root system once the hydrangea is mature. This increases the hydrangea’s resistance to drought and therefore decreases the risk of leaves and flowers turning brown.
- If it is not practical to replant your hydrangea, then what I recommend you do instead is give the soil a thorough watering, ideally with a hose to ensure the soil around your hydrangea is evenly moist to a really good depth, as hydrangea roots are extensive.
- I Always give my hydrangea a really generous soak as this encourages the roots to grow deeper in the soil to access the moisture which increases its resistance to drought. Watering too lightly results in the hydrangea roots growing near the surface, which leaves them vulnerable in Summer and increases the risk of the leaves and flowers turning brown.
- I can assure you that the best thing you can do is apply a 2-inch layer of mulch (compost, leaf mold, or well-rotted manure) to the surface of the soil around your hydrangea. The mulch helps to conserve the soil’s moisture to create the optimal balance of moisture.
- Ensure that your hydrangea is out of the way of wind, as it saps too much moisture from the leaves and turns the leaves and the flowers brown. Hydrangea grows naturally in woodland so planting hydrangea under a tree is an effective strategy to increase shelter and provide the right conditions.
Pro tip: To shelter your hydrangea from wind, what I like to do is use bamboo as a windbreak as bamboo plants are very hardy in terms of tolerating wind, which helps you create the right environment for your hydrangea.
In terms of the brown leaves and flowers, I cut them back with pruners at any time of year or wait for them to fall naturally.
However, I should emphasize that light pruning is best and caution against any heavy pruning as this can remove the growth from which the flowers are displayed.
I should also emphasize the importance of regular watering and the use of mulch.
We need to remember that hydrangeas are woodland plants and hydrangea naturally have a mulch of fallen leaves on the wood land floor every year which helps conserve moisture so adding a layer of leaf mold or compost can really help to emulate the moisture retentive soils to which hydrangeas are adapted.
Once the hydrangea is growing in its preferred conditions the leaves should stay green, although the flowers usually do not revive and you may have to wait until they bloom the following year.
(Read my article, how to revive a wilting hydrangea).
Why Are My Potted Hydrangea Leaves and Flowers Turning Brown?
As I’m sure you can imagine, the reasons for potted hydrangea leaves turning brown is largely the same as why any hydrangea turns brown.
However, there are a few characteristics pertaining specifically to growing hydrangeas in pots that can increase the risk of brown leaves and flowers that I should tell you about…
Potted hydrangea leaves turn brown most often because they are planted in pots that are too small and dry out too quickly. Hydrangea has extensive root systems and a high demand for moisture in the soil. If the soil dries out then the leaves wilt or curl up and turn brown as a sign of stress.
Hydrangea roots tend to spread wide more then the do deep so, if the pot is too small and narrow then it has less capacity for potting soil which retains moisture.
Whenever I see a hydrangea with brown leaves in a pot, I always check the roots as they are usually pot-bound and therefore have less access to moisture.
It should be noted that pots also require watering far more often than hydrangeas planted in the garden, as pots can dry out very quickly on hot days and result in a dying hydrangea.
The Solution…
- The first thing that I would do is replant the hydrangea in a pot that is at least 12 inches across with the same proportional depth. A pot of this size ensures that the hydrangeas have enough soil for the roots to access the required moisture and nutrients. However, as the hydrangea matures, it is worth checking to see if the roots are pot-bound as the root system can be very extensive, in which case, plant the hydrangea in an even larger pot.
- I personally recommend Adding some leaf mold to the potting mix. I have seen great results when I do this because Leaf mold has an exceptional capacity to retain moisture (even more so than compost) to help ensure the optimal moisture balance for your potted hydrangea.
- Give your hydrangea a good soak as often as required so that the soil is consistently moist. Water the hydrangea thoroughly so that excess water trickles from the drainage holes in the base of the pot to ensure the soil is evenly moist and that the water has reached the roots where it is required.
- At the hottest times of the year, I find I have to water potted hydrangeas every day to prevent the leaves from turning brown. Hydrangeas have a high demand for moisture because of their large, plentiful leaves. In cooler more temperate climates watering hydrangeas once or twice per week in the Spring and Summer is usually the right amount to achieve the optimal moist soil conditions.
With a larger pot and more frequent watering, the hydrangea should have all the resources it requires so that the leaves stay a healthy green rather than turn brown.
We still need to ensure that the pot is in a sheltered area, out of the wind, and in dappled light or morning sun followed by afternoon shade.
Again I recommend, clipping back any brown leaves or flowers at any time or you can leave them for the hydrangea to shed naturally.
Too Much Sun Scorches Hydrangea Leaves and Flowers Brown
This is a really common mistake I see people make, which is why I always think we need to know how hydrangeas grow in the wild so we can emulate theses conditions in our gardens…
Hydrangea leaves and flowers turn brown and scorched if they are in too much sun. Hydrangeas are adapted to living under a tree canopy with dappled light throughout the day and do not tolerate being in full sun which not only scorches the leaves brown but can contribute to drought stress.
Hydrangeas are woodland plants that thrive under trees which protects them from excess wind, sun, and frost damage in Winter.
Whilst hydrangeas can grow in full shade, I observe that they tend to grow green foliage but with fewer flowers.
The key to growing hydrangeas, (ensuring a good display of flowers and avoiding scorching the leaves brown) is to find the optimal balance of sun in your garden.
Pro tip: I have learned that hydrangeas grow best when in an area of morning sun followed by afternoon shade or in dappled light throughout the day.
This balance of sunlight and shade ensures the hydrangeas have enough energy to produce flowers yet are protected enough from intense sun and heat to prevent the leaves and flowers from turning brown and wilting.
It is in these conditions that I see the healthiest hydrangeas with the most plentiful flowers.
The Solution…
To create the optimal balance of sun and shade and avoid the leaves turning brown, you can transplant your hydrangea under a tree to replicate its natural conditions of dappled light or attempt to shade it with some taller plants such as bamboo.
Or you can find a shadier area of the garden. Our goal should be to ensure that the hydrangea is shaded during mid-day and afternoon when the sun is at its most intense and temperatures are at their highest.
Not only will this prevent the leaves from scorching brown, but also mitigate drought stress at the hottest times of the day.
Trim back any brown leaves and flowers or wait for the hydrangea to shed them naturally.
Hydrangea Leaves Turning Brown on the Edges (Fertilizer Burn)
If your hydrangea leaves are brown at the edges this is often because of fertilizer burn from using fertilizer too often or in too high concentration. Hydrangeas require a slow-release fertilizer as an abundance of nitrogen causes the leaves’ edges to turn brown as a sign of stress.
Hydrangeas are relatively heavy feeders that grow best in fertile soil and benefit from the use of fertilizer in the Spring to support healthy growth and display more flowers.
However, hydrangeas are very sensitive to overuse of fertilizer causing their leaf edges to turn brown and crispy and it can reduce the display of flowers.
When I was a landscape gardener I observed that the owner of the house had applied lawn fertilizer right before deluge of rain! I worked out that the rain dissolved the water soluble nitrogen in the fertilizer which ran off the surface of the lawn and around the garden boarder where the hydrangea was planted!
Th leaves turned brown at the edges in the following weeks, but a lesson was learned!
It is important for us to acknowledge that more is not better when it comes to fertilizer as slightly too much fertilizer can promote foliage growth at the expense of flowers and applied too much or too often results in leaves with brown edges and cause the hydrangea to droop.
The Solution…
The key is to find the right kind of fertilizer for hydrangeas.
Personally, I recommend miracle-gro all-purpose granular fertilizer which contains all the nutrients the hydrangea requires for growth and flower at the right concentration to avoid the leaf edges turning brown.
The granulated formula releases the nutrients slowly to mitigate any risk of fertilizer burn.
(Read my article, why isn’t my hydrangea flowering?)
Cold Weather (Hydrangea Buds and New Growth Turning Brown)
This is a really annoying one and it has happened to me several times!
The new leaves and flower buds of hydrangeas turn brown if they are exposed to a late Spring frost or cold Winds. The newly emerging buds and leaves are particularly tender and especially vulnerable to damage from a sudden cold snap, causing the buds to turn brown and die back.
As we talked about, hydrangeas naturally grow in sheltered areas under trees, which buffer harsh cold winds and create a more stable micro-climate in which the new flowers can emerge without such a significant threat of frost.
When the new buds and leaves of hydrangeas become frost damaged, the leaves turn brown and the buds can turn to a mushy texture.
I find it is usually the outermost growth that is most badly affected as it is more exposed to the elements.
Unfortunately, the damaged flower buds are not then able to flower and the newly emerging growth most likely will not recover.
The Solution…
Frost damage to hydrangea flower buds and leaves is more prevalent where the hydrangea is more exposed, so I advise planting or transplant your hydrangea to a more shelter part of the garden, by your house or near some other plants and hedges.
I love to use hedges as hedgerows in particular are excellent at buffering wind as they provide a wall of protection for your hydrangea and can also help to mitigate the effects of frost.
However, once the flower buds and newer leaves have turned brown, I’m afraid there is not much you can do to revive them. Therefore, I would cut back any growth that has been damaged by the frost and trim it back to healthy growth.
Hydrangeas often have developing flower buds further down each branch which is naturally more protected the the flower buds on the outermost part of the plant and they usually survive a frost.
This means your hydrangea can still flower, although it may be much later and with fewer flowers emerging, so with some patience, there should still be some good blooms on display in the Summer.
Pro tip: This is a great tip taught to me by specialist hydrangea growers. Use horticultural fleece to protect your developing hydrangea flower buds if there is a late frost forecast. I often wrap my hydrangea up in fleece in early Spring when the buds are emerging as since I have done this my flowers do not turn brown and I get to enjoy the blooms!
(Read my article on how to revive a dying hydrangea).
Flowers and Leaves Turning Brown From Overhead Watering
I think we have all made this mistake at some point in our gardening journey!
Hydrangea flowers and leaves can turn brown from excessive overhead watering which can damage the delicate flowers and promote the conditions for leaf spot fungus which appears as small brown spots on the hydrangea leaves and can cause them to drop off.
When watering hydrangeas, always water at the base of the plant rather than onto the foliage and flowers. Hydrangeas are hardy enough to tolerate some water on their leaves from rainfall but excessive watering of the leaves in the Summer is usually what promotes the conditions for leaf spot fungus to spread.
Leaf spot is a fungal disease that does not kill the hydrangea, but the stress of the disease can reduce its overall growth and reduce the number of flowers on display.
Eventually, the leaves can fall off, and it’s important to clear them up and burn or dispose of them to try to limit the spread of the fungus.
So what I do is Water at the base of the hydrangea as an effective way of mitigating the effects of leaf spot fungus and preventing it from spreading to other parts of the plant.
The best way I’ve found from experience to robustly solve the problem (as it usually comes back every year, if it is left untreated) is to use a fungicide spray and spray it with several applications for around 14 days in between, although you should always follow the manufacturer’s instructions.
(Read my article, why are my hydrangea flowers turning green?)
Key Takeaways:
- Hydrangea leaves and flowers turn brown due to drought, excessive wind, and too much sun. Hydrangea prefers to grow in sheltered areas with the dappled sun, in moist soils, and protected from the wind. Not enough moisture around the roots causes the hydrangea leaves and flowers to wilt and turn brown.
- Potted hydrangea leaves and flowers turn brown when they are planted in small pots, as smaller pots dry out too quickly for the hydrangea roots to draw up moisture. Hydrangeas have an extensive root system and require consistent moisture to prevent the leaves and flowers from turning brown.
- Applying too much fertilizer or applying it too often causes the hydrangea’s leaf edges to turn brown and crispy. Hydrangea roots are very sensitive to excess fertilizer so it is important to apply a slow-release fertilizer at the start of Spring to prevent the leaf margins from turning brown.
- A late frost in Spring can cause the flower buds and emerging foliage growth of hydrangeas to turn brown and mushy. The new growth is tender and more vulnerable to frost damage. Brown, mushy hydrangea flower buds do not develop into flowers and should be cut back.
- Leaf spot fungus causes brown spots on the leaves of hydrangeas and is usually caused by excessive watering on the leaves of the hydrangea. Too much moisture on the leaves promotes the conditions for the fungal disease to thrive and causes brown spots on the hydrangea with fewer flowers.
