Problems, pests and diseases

Hydrangea leaf problems

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Hydrangeas come in many varieties and are very easy to grow. You can choose from a big leaf variety or a panicle style depending on what type of display you want. But of course, regardless of the variety, the last thing you want is for your display to be hindered by leaf problems.

Common leaf problems can include diseases, environmental problems, even pests.

Environmental Problems

Environmental problems typically relate to issues of bad air circulation or problems watering. If you don’t prune enough or you don’t space your hydrangea plants apart enough they can grow too large for their space and cut off proper air circulation which leads to unnecessarily moist conditions. This often results in issues with an appearance that manifest on the leaves. 

Powdery mildew is a very common problem that doesn’t harm the plant but does impact the appearance. If your hydrangea isn’t producing flowers or you notice a literal white, powdery mildew on the leaves, it is likely powdery mildew that is causing the problem. You might see this when you have bad air circulation or very damp conditions and you need to get rid of any unnecessary humidity and increasing the air circulation to help treat the problem. You can also spray plants with a fungicide that treats mildew at the first signs to help prevent it spreading.

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Leaf diseases

Hydrangea leaf spot

Leaf spot disease

The most common of leaf diseases that you will see with your hydrangea is called leaf spot disease. This is sometimes known as foliar disease which is often caused by a fungal infection brought about by moist conditions. When you have particularly warm-weather it can result in leaf spots. These spots are just that, spots that appear on the leaves.

The best way to treat this problem is to prevent it in the first place by making sure you only water your hydrangea in the morning or in the evening, and that when you water you do it at the base of the plant rather than from above. The reason for this is that water remaining on your leaves after you have watered the plant or after heavy rain can remain in place, build-up, and result in fungus. If you have watered or it has rained and there is water on the leaves you can gently shake your plan to get them off.

But if the problem is already here a fungicide will help you get rid of it.

Bacterial leaf spot

Hydrangea pests and diseases

Similarly your hydrangea might be suffering from bacterial leaf spot. This doesn’t form the soft leaf spots but rather a discolouration on your leaves. This one is more problematic than a fungal infection because it can actually kill your plant. The symptoms can manifest in a multitude of ways and they start with black-edged lesions on the leaves or dark brown lesions with a yellow tinge. Most of the time the spots are irregular and quite small. You might notice them at the bottom part of the leaves or the very top. Eventually, they will dry, turn brown, and fall off. Wet and cool conditions encourage bacterial growth and the bacteria can get splashed on your hydrangea leaves from other debris or nearby plants. If you already noticed the symptoms you can use a bactericide to treat the condition and prevent it from spreading not only to more parts of your hydrangea but to other plants in the nearby vicinity.

Pests that affect hydrangea leaves

Look out for pests in the garden such as aphids, slugs and snails

There are problems with pests now and again that can affect the leaves. Some pests are not as intrusive as other pests such as spiders. If you see spiders on your hydrangea if you can leave them alone because they feed on other insects. But spider mites actually feed off of your leaves and harm the plant.  The problem with spider mites is that most people don’t see them until the problem is quite significant because they are so small. You have to get up close to the leaves to notice the little small, red bugs. You can spray them off with water when you see them, mixtures of water and citrus oils as deterrents, or you can use pesticides.

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The same issue comes from aphids and whiteflies. These are equally small and difficult to see but they remove the sap from the tissues in the leaves until such time as your leaves turn yellow and fall off prematurely. You can remove these with a mixture of water and dish soap but don’t do it when the sun is out and overhead or it can squirt your leaves. You can also just use water with high pressure to wash them off the leaves, or a pesticide.

Whatever the leaf problem on your hydrangea, the key is to fix it as soon as you can. This prevents any harmful issues from getting worse.

Image credits –

Last update on 2021-10-16 / Affiliate links / Images from Amazon Product Advertising API

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