Skip to Content

Why Are My Hosta Leaves Splitting?

Hostas are wonderful plants that require a little attention to be healthy. Today we are going to look at one of the fairly common problems that arise during the growing process.

The scorching sun, strong winds, and drought are the main causes of the splitting of the hosta leaves. In addition, mechanical damage, low humidity, and a lack of nutrients cause the leaves of the hosta to crack.

Too much direct sunlight

what causes slits in hosta leaves

The scorching sun is one reason why hosta leaves split. Exposure to the sun’s rays causes the tissues to fail and crack.

In addition, brown or transparent spots may appear on the leaves. These are typical symptoms of sunburn.

Hostas are known to prefer reflected sunlight or the dappled sun to direct sun. Some varieties can tolerate a few hours of direct sun while others cannot tolerate it at all.

However, it is not always possible to get the right sun exposure. Also, the sun has different intensities in different parts of the country and at different times of the year.

How to fix

Shade the hosta with a screen or an umbrella for times of intense heat and scorching sun. Water once with an extra 1-2 gallons of water.

Next spring, transplant the hosta to a shady location. Or plant a tall plant on the south side of the bush to protect it from the mid-day sun.

Read more: Planting And Caring For Hosta

Heavy winds

why do hosta leaves split

Because the hosta leaves contain a lot of water, they have internal pressure. As a result, they are quite brittle, especially when exposed to strong winds.

Wind can force a leaf to fold crosswise or lengthwise. If this happens abruptly, the leaves will crack. There may be several parallel cracks.

Sometimes even a part of the leaf may tear off. It is also very rare but the leaf petioles may break.

How to fix

Plant the hostas in a location that is sheltered from strong winds. If necessary, transplant the hosta to a more sheltered location.

Don’t overfeed or overwater the hosta. This will make the leaves grow larger but will also make them brittle.

The split leaves will never regenerate, but new, undamaged leaves will appear after a while.

Dehydration

what causes hosta leaves to split

Lack of water can also cause cracks, or more accurately, tears in the leaves. This is because dehydration causes the leaf plate to become soft, and it can tear under its own weight or for other reasons.

In most cases, the hosta is able to extract the necessary amount of water on its own. But if it is a newly planted hosta or the drought is very severe, there may not be enough water. The same can happen if the hosta is growing in sandy soil.

In addition to tearing on the leaves, brown spots may appear on the leaf edges. The tips of the leaves may curl.

How to fix

Water the hosta when the soil is more than 2 inches dry. Watch newly planted hostas especially closely in extreme heat and keep them from suffering from thirst.

If your hosta is growing in sandy soil, transplant it to soil improved with organic matter. Be sure to mulch the root zone with organic mulch, read more about mulching in How Do You Mulch Around Hostas?

Low humidity

why are my hosta leaves cracking

Too dry air is always bad for the appearance of the leaves. Symptoms can vary and one of them is cracking.

This is most common during hot summers and dry weather. In addition, if the soil is sandy, the water quickly goes deep. As a result, the surface is too dry.

Other symptoms can be partial browning of the leaves. Marks may also appear on the stems.

How to fix

Provide additional shade over the hosta during hot or dry weather. Next spring, transplant the shrub to a more shady location without direct sunlight. In a shady spot, the humidity level of the air is optimal for the hosta.

Avoid frequent watering to increase humidity as this will lead to root rot. Moistening the leaves while watering will not solve the problem and will only cause brown spots.

Lack of nutrients

hosta leaves splitting

Lack of nutrients in the soil can lead to discoloration or yellowing of the leaves. Leaves that have little chlorophyll are more susceptible to splitting.

Poor or too alkaline soil is the main cause of starvation. Poor soils include clay or sand. In the case of alkaline soil, the plant is not able to absorb the nutrients in it.

As a result, the leaves turn yellow with green veins. There may be cracking or slits in the areas of yellowing.

How to fix

Test the pH and if it is much higher than 7.0, add an acidifier to the soil. A soil pH test kit and acidifiers are commercially available.

Feed the hosta once a year with a slow-release multipurpose fertilizer. Do this only at the beginning of the season, avoid fertilizing later than July. Mulch the hosta with fresh, quality compost.

Avoid using fertilizers with too much nitrogen (more than 20), as this can lead to brittle leaf petioles.

Mechanical damage

why are my hosta leaves splitting

A final cause of cracks in hosta leaves can be mechanical damage. This is usually the most common cause.

First of all, dogs can play around the hosta and damage the leaves with their paws. Even if you don’t have a dog, a neighbor’s dog can do this.

Cats can also cause minor damage to the leaves. This also applies to all wild animals, including birds.

The second source of damage can be you or your children. You can unconsciously damage leaves when you are working in the garden. Or your gardener, for example, can easily cut hosta leaves with a string trimmer.

How to fix

Make a low barrier around your hostas. This will prevent damage in most cases.

You can also move your hostas to the back of the garden away from the sidewalk or seating area.

When working in the garden, be as careful as possible to avoid damaging not only the hostas but other plants as well.

Remove badly damaged leaves. Very quickly the hosta will produce new ones.