4 Reasons Behind Hydrangea Leaves Turning Black with Remedies


The black leaves on hydrangea leaves can indicate that the plant is in serious need of help. And if you choose to ignore it then it might slowly kill your precious plant.

But who is the culprit behind the gorgeous hydrangea leaves turning black?

Well, there is more than one factor to blame here. But don’t worry; we’ll go through each of the problems one by one. And we’ll also stop to talk about their solutions.

So, buckle up, folks. We’re about to start the journey.

Photo of Hydrangea Bushes
Photo by Tbel

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All the Reasons Behind Hydrangea Leaves Turning Black

While there are several reasons behind hydrangea leaves turning black, we narrowed it down to 4. These 4 reasons are the most common ones out there.

Chances are one of these culprits are the reason behind your plant’s suffering. Do you want to take a closer look at these cases? Then scroll down a bit. We’ll start discussing the problems right away.

Reason 1- Deadly Disease

The most alarming thing about hydrangeas is that they are prone to fungus attacks. In fact, there are various fungi out there who are merely waiting for the chance to attack this defenseless being.

Now, different fungi result in different symptoms. But the gray mold and powdery mildew are the ones that cause black spots on the leaves of hydrangeas.

And if you see the foliage turning black, you can be sure that it’s the root rot fungus. They’re famous for their attacks from beneath the ground.

Moreover, during rainy seasons water gets stored up near the soil. That’s what makes things worse for the plants. This is because the fungus can thrive on moisture and multiply rapidly.

Then they attack in groups, and your plant becomes the victim in this case.

Solution- Apply Fungicide or Other Natural Remedies

However, there is no need to get disheartened. That’s because you can save the plant before it’s too late.

All you have to do is notice the symptoms and then apply a fungicide to kill the fungus. But if you don’t want to use a chemical on your soil, you can go for natural remedies.

These include compost tea, liquid kelp, and even garlic oil. You can use anything from this list.

Garden Safe BrandFungicide3 Concentrate

Spectracide 100507462 Immunox Multi Purpose Fungicide Spray Concentrate

Bonide (BND862) – Fungal Disease Control, Mancozeb Flowable with Zinc Fungicide Concentrate

Reason 2- Insect Invasion

Take a stroll down your garden and you’ll find that many bugs and insects are roaming around in the garden. Despite looking harmless they can pose serious danger to your plant. And the most common criminals are the aphids.

These insects tend to survive by sucking sap and eating the green tissues of healthy plants. And at the end of the day they excrete a residue known as honeydew.

This might sound delicious, but it really isn’t. In fact, it lures out a fungus known as sooty mold. These fungi, later on, surround the honeydew and form a black coat on the hydrangea leaves. Insect invasion can turnout deadly for your plants.

Solution- Spray Neem Oil on the Plants

As for removing the aphids, you can spray it with neem oil. This essential oil repels the aphids like it’s a demon running away from holy water.

Moreover, this repels a lot of bugs in the garden. So, be sure to apply it now and then for some healthy-looking plants.

Reason 3- Excessive Watering

We can all agree that too much of anything is bad for us, right? Like that even water can become a problem for the plants when it’s poured in bulk.

That’s right; excessive water can also cause black marks on hydrangea plants. This happens because the plants cannot soak up the extra water.

Thus, it remains on the soil and continues to damage the roots. At one point, the root starts to turn black. But it does not end there.

The damage slowly crawls up to the upper parts. And it slowly reaches the leaves. Moreover, the water can also help fungi grow.

So, it’s crucial to maintain the optimum water level for plants like hydrangea.

Solution- Install a Drainage System

Excess water is not a huge problem. You can take care of it by watering the plant only after the soil has dried up.

This ensures that water does not get the chance to lie around and help give birth to fungus. Another way to sort out the problem is by installing a sound drainage system.

The handy tool can help you remove excess water from the soil. This way, your soil will remain dry all the time. So, you won’t have to worry about soggy soil ever again.

Reason 4- Too Much Fertilizer

Did you know that too much fertilizer can also damage your plants? Yes, this happens because the fertilizer ends up burning your plant.

It starts from the root but eventually makes its way up to the leaves. And that’s when you see black spots on your leaves. On top of that, this can be quite problematic for the plant.

So, you need to act fast to cure this problem.

Solution- Dig the Soil and Pour Water into the Ground

Since the problem lies in the root, you should dig up the soil and remove the plant from it. Then you can plant it somewhere else for a temporary period.

And to treat the soil, you have to add water. Now, don’t go overboard and add too much of it. Only apply as much water as the soil can hold, and you should be good to go.

To Wrap Up

Now you know that the fungus, insects, fertilizer, and even water are the 4 main reasons for hydrangea leaves turning black. Well, with this info, you can narrow down your suspect.

And then move on to curing the problem of its root. But if you have any trouble along the way, do leave a comment below. We’ll love to help you out.

Take care, guys. See you next time. Tata!

As an Amazon Associate I earn from qualifying purchases.

Celina Nance

It’s been a life-long wish of Celina Nance to have a lawn full of colorful flower beds. But living in Arizona city, that seems kind of impossible. But Celina Nance didn’t stop and created a full-form balcony garden instead. And she often shares stuff that she does/solves/innovates throughout the journey.

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