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What Causes Holes In Hosta Leaves?

The leaves of the hosta look amazing, which is very appreciated by a huge number of gardeners. However, other creatures find hosta leaves as a delicacy. Consequently, the leaves are permanently damaged.

The main causes of holes in hosta leaves are slugs and cutworms. To prevent holes in hosta leaves, drench the soil around with a 10% aqueous solution of ammonia and sprinkle some iron phosphate granules. Also, spray the leaves with insecticide.

This is a brief summary of the two main causes, but there are others. Next, we’ll look at all the main causes of holes in hosta leaves in much detail and you’ll learn how to stop it.

Slugs and snails

holes in hosta leaves due to slugs


Slugs are a real disaster for hosta fans. They can make a sieve out of the leaves. The hosta is unlikely to die, but it will look terrible.

When it’s warm and humid, the slugs multiply like crazy. As a result, there are so many of them that it is very difficult to control them with homemade remedies.


The main symptom of slug damage is holes in the leaves. The holes can vary in shape and size.

A typical slug hole is about a quarter of an inch across. Very often slugs eat leaves between veins, then holes are long but narrow.

There are also baby slugs and small snails. They leave tiny holes on leaves no larger than a tenth of an inch across.

How to treat and prevent

The first thing to do is to dilute ammonia in water, in a ratio of 1:10. Next, water the soil around each bush. This will kill the slug eggs in the soil.

Next, put some iron phosphate pellets near each hosta. This will kill the adult slugs that are constantly moving around.

Read more: Slugs and snails on hostas


holes in hosta leaves due to cutworms


Cutworms are moth larvae and can be found in both gardens and farmland. In fact, it is a serious pest of both ornamental plants and agricultural crops.

In general, it is a larva several inches long and rather thick. The color is dark brown or gray.


This pest can cause significant damage to the hosta. Cutworms eat mostly leaves but can damage stems as well.

As a result of their activity, holes are formed on the leaves noticeably larger than those caused by slugs. But sometimes cutworms may eat a leaf between the veins, making a long hole.

How to treat and prevent

Use diatomaceous earth against cutworms. Just sprinkle some of this product around the hosta bush. When the larva touches the diatomaceous earth it will dehydrate and die.

You can also use insecticides. There are a number of chemical and biological insecticides that can handle this pest.


The diet of many insects is plants. Because hostas have large and juicy leaves, they often become food for insects.

Many different bugs like to eat hosta leaves. Among them are grasshoppers, leaf beetles, weevils and others.


All insects leave different marks on the leaves. It can be as a biting leaf edge or holes. Even the petioles can be damaged.

Usually, the insects are immediately visible on or near the leaves of the hosta.

How to treat and prevent

You can use neem oil or insecticidal soap against most bugs. Simply spray the leaves 1-2 times at 7-day intervals and the problem is solved.

In some cases, you need to use systemic insecticides. This usually refers to grasshoppers or weevils.

Read more: What insect eats hosta leaves?


holes in hosta leaves due to fungus


Fungal diseases are a common concern for almost all gardeners. Fungal pathogens can affect almost all plants and spoil their appearance.

In late spring or early summer, when the weather is warm and humid, the fungus spores get on young leaves and begin to sprout. Young soft leaves are very susceptible to fungal disease.


The fungus usually causes brown or black spots on the leaves. But sometimes small holes may form in place of the spots.

The difference between the fungal holes and those left by pests is the brown or dark gray edge. In addition, fungal holes are usually circular in shape, while in other cases the holes may have different shapes.

How to treat and prevent

The most effective way to get rid of the fungus on the leaves is to spray them with fungicide. Since there are so many fungal diseases you need to use a multi-purpose fungicide or copper fungicide.

Just dilute the product as indicated on the label and thoroughly spray all the leaves. Wait about 10 days and spray again.


Herbicides are very handy for controlling weeds in the garden. However, they have a drawback. If the herbicide gets on the leaves of ornamental plants, it can damage them.

If you or your neighbors have treated your yard with herbicide, you may notice damage to hostas and other plants after a few days. This happens because of improper use.


Dry, light brown spots appear on the leaves. Very often only one side of the shrub is damaged.

Over time, the spots turn into holes. The holes are usually not very big.

How to treat and prevent

To prevent damage, do not work herbicides near the hosta. Ignore the text on the label that says herbicide is safe for ornamental plants.

If damage is done, cut off badly damaged leaves. Water the hosta with liquid fertilizer. It will recover after a while.

Sun damage

holes in hosta leaves due to sun damage

Sun damage

Hostas do not like direct sun and prefer to stay in the shade most of the day. If you plant them in a sunny spot, the leaves can get sunburned.

Yellow hostas, for example, can tolerate some direct sunlight. Blue hostas, on the other hand, hardly tolerate direct sun.


The sun can burn the leaves, resulting in large brown spots. Over time, a hole will appear in the center of the spot. Sometimes half of the leaf may simply disappear.

How to treat and prevent

Avoid planting hostas in full sun. In general, most varieties can tolerate about four to five hours of the morning sun.

If a hosta gets sunburned, put some shade over it. In the spring or fall, transplant it to a shady location.

Read more: How much sunlight can hostas tolerate?