What Is Eating My Hydrangea Leaves?

Hydrangeas are deciduous shrubs with beautiful flowers that bloom in summer and spring. The flowers are easy to keep, but pests can eat their leaves. So, what eats hydrangea leaves and what can you do to save them?

Pests like slugs, rose chafers, caterpillars, spider mites, aphids, beetles, etc., eat Hydrangea leaves. The bites leave different marks on the leaves, which helps you identify the culprit bug and determine the most effective way to control it.

The pests may not kill your plant, but they can ruin the look of the leaves. Therefore, it is important to stop the infestation. This article lists the pests that eat the leaves and ways to stop them.

Table of Contents

Types of Pests That Eat Hydrangea Leaves

As mentioned, many types of pests like to eat Hydrangea leaves. They usually become adults during the blooming season and leave after doing the damage as fall sets in.

Let’s talk a bit more about these pests and how to eliminate them.

Rose Chafers

These are a type of beetle. As the name suggests, rose chafers mainly attack roses, but they also like to eat Hydrangeas.

These pests eat both the bloom and the leaves. They create holes of different sizes in leaves, causing a condition known as leaf skeletonization. These small insects may not kill the plant, but they can ruin the beauty of the foliage entirely.

Rose chafers are more minor than Japanese beetles, with long orange legs and tan or green bodies. They grow in dry sandy topsoil that receives sunlight and are most common in Minnesota, where they invade gardens in summer.

How To Control Rose Chafers Infestation

You may not be able to get rid of rose chafers entirely if the adults have already attacked the plant. However, you can do something to reduce their numbers.

Here are several ways to control the infestation:

Pick them out with your hands and dump them in soapy water to kill them. This can be time-consuming, but it’s worth a try. The best time to pick them up is in the morning when they are relatively lazy.
Use small handy vacuum cleaners that can suck the pests.
Grow clover in your garden or lawn; it keeps Rose Chafers away.
Place an insect net over your Hydrangea shrubs if the pests have already invaded the garden.
Use topsoil without sand.
Since Rose Chafers like sunny surroundings, you can plant trees and shrubs to give the soil some more shade.

Slugs

Slugs become a problem during wet and cool conditions. They like moisture in the soil and vegetation-rich gardens. These pests feed on young Hydrangea leaves when they can’t find any decaying substances.

Slugs leave a trail of mucous on the leaves. So if you see the shiny trail, you can pin the problem on these soft-bodied mollusks.

You can also catch slugs red-handed if you check your plants’ leaves at night because they are nocturnal feeders. They usually start eating the leaves at their edges and work their way inwards.

How To Get Rid of Slugs

Getting rid of slugs may not be as difficult as some other pests. Just like Rose Chafers, you can pick slugs with your hands at night; that’s when they’re most active.

If you don’t have the time for handpicking the slugs, there are other ways to deal with them.

Slugs have very soft bodies that can take damage quickly, so you can control them by building a wall or barrier around your pot or garden area. You can use broken egg and oyster shells, sawdust, gravel, or anything prickly for the barrier.

You can also spray your plants with soapy water to keep the slugs away. Getting rid of mulch can also help, but this might not be an option in some gardens. Mulch and plant debris attract slugs, especially during the rainy season. So if you can get rid of it without affecting your garden’s health, it’s worth a shot.

Last but not least, you can set up traps to trap slugs. You can purchase a beer trap or make one at home.

Spider Mites

Spider mites are arachnids that feed on saps and lay eggs on the leave’s underside. Their trademark is the web they wrap around the damaged area, causing the leaf to decay, turn brown and wither.

Spider mites infestations usually happen anytime between July and September. That’s not by coincidence. These pests thrive in warm and dry environments, and most parts of the US have these conditions between July and September.

How To Control Spider Mites

Here are a few effective ways to control Spider Mites:

Bring some ladybugs or similar predators that feed on spider mites into your garden. The best thing is that these predators won’t harm your Hydrangeas.
Spray the Hydrangea with a mixture of insecticidal soap and water. You can spray the leaves at least once weekly until the infestation goes away.
Take away their dry and warm conditions by spraying water on the leaves.
Use pyrethroid pesticides. They are a safer option than synthetic pesticides.

Caterpillars – Hydrangea Leaf-Tiers

Hydrangea Leaf-tiers are tiny brown caterpillars that eat the leaves. As a defense mechanism, the caterpillars tie or glue the leaves together, giving themselves shelter against predators.

This type of caterpillar infestation turns the leaves brown, destroying their beauty. However, Hydrangea leaf-tiers do not kill the host plant.

These caterpillars take ten days to become Chrysalis and then morph into adult moths after another seven days if you don’t get rid of them. They are common in Ohio, so you might want to be on the lookout if you reside in that state.

How To Get Rid of Caterpillars

It is important to control Hydrangea Leaf-tiers as soon as you notice tied-up leaves because the moths they spawn from lay eggs in the fall season. The eggs then hatch and invade your garden again during the blooming season.

If the attack is mild, you can handpick the caterpillar by opening up the tied leaves. However, you may have to do more if the infestation is heavy.

Let’s see some steps you can take to get rid of the caterpillar:

Spray the Hydrangea leaves on both sides with a solution of water and Bacillus thuringiensis. This solution is most effective right after the eggs hatch.
Cut down your plants at the start of Spring. The moth that spawns hydrangea Leaf-tier lays eggs in late fall on the stem of the plant. As such, you can proactively control infestations by cutting down your plants so that only about four inches of stem sit above the ground. Just ensure that you cut as soon as Spring starts, so they don’t get a chance to lay eggs.

Aphids

Aphids are tiny bugs that you may find in different colors – yellow, green, or brown. These pests have “mouths” that suck the juices from the leaves, causing them to curl, dry, and turn yellow.

Aphids attack younger plants when they are tender enough for the bugs to penetrate. The pests are good at hiding from the sun, so you may find them on leaves that do not receive too much light.

Aphids have an interesting defense mechanism. Their waste has a high sugar content that attracts ants. Though they do not damage the leaves, the ants protect the pests from many predators.

How To Control an Aphids Infestation

Here are some methods you can use to prevent an Aphids infestation:

Use soil that drains well, but don’t let it dry too much.
Spray the Hydrangea leaves with insecticidal soap and water solution.
Spray the leaves with water.
Brush the aphids away with your hands if you have a light infestation.

Four-Lined Plant Bug

Four-lined Plant Bugs are tiny white pests that like to feed on Hydrangea leaves. Even though these pests do not cause extensive damage to the plant, they ruin the foliage look. Four-lined bugs leave little brown pockmarks or holes on the leaves.

The good news is that the fully grown bugs do not feed on leaves for more than a month and leave without significant damage. However, they leave their eggs behind, which hatch at the beginning of Spring.

How To Get Rid of Four-Lined Bugs

Removing four-lined bugs is not tricky, so you do not have to worry too much. Here are a handful of things you can do to control these pests:

Spray with soap water; it kills these pests.
Spray the Hydrangea leaves with insecticides.
Bring in some natural four-lined bug predators.
Prune the damaged leaves, allowing newer ones to grow.
Spray the Hydrangea plant with the Monterey LG 6299 Horticultural Oil (available on Amazon.com). It’s very simple to use and effective against a wide range of insects.

Scale

Scales are white pests with brown heads that grow on the underside of the hydrangea leaves. They suck the plant’s sap and deprive it of its vigor. You can see the pests with your naked eyes at the beginning of Summers.

Scales do not necessarily eat the leaves. However, they cause leaves to fall off the plant, affecting the foliage.

How To Control Scale Infestation

You must eliminate scale infestation if you want healthy-looking happy Hydrangea plants in your garden. Here’s how you can control them:

Spray the plant with pesticides in July when Scales are relatively weak.
Remove the plants with a heavy infestation and replace them with new ones.
Spray Hydrangea leaves with water at least once a week.
Introduce ladybirds and similar-scale predators to your garden.

Conclusion

Hydrangea pests attack the leaves of the plants during the blooming season. Even though most of them do not cause fatal damage to the plant, they can ruin their beauty and vigor. Hopefully, reading this post has given you an idea of what’s eating your hydrangea plants and what you can do to remedy the situation.