Hostas are shade plants, but there are many varieties that can tolerate direct sun for several hours a day. However, in southern states, even such varieties can burn in strong sun and drought.
To fix the hosta leaf scorch, water as soon as the soil is more than an inch dry. Use at least 1 gallon of water for each hosta. Also, give it as much shade as possible and transplant it to a shady spot as soon as possible.
In the following, I will explain in more detail what you need to do to fix and avoid sunburn.
Give enough water
If you notice symptoms of scorch on your hosta leaves, the first thing to do is to water it well.
Give enough water to soak the soil to its full depth and at least 2 feet in diameter. Try not to form a swamp, however. To do this, water two or three times at one-hour intervals with small amounts of water.
The total amount of water should be 1-2 gallons, depending on the size of the bush.
I recommend waiting until the evening before watering. You don’t want to water the plants in the heat, as most of the water dries out before it has time to get to the roots.
Going forward, make sure that the soil around the plant does not dry out more than one inch. Keep it moist, but not too wet.
However, watering alone cannot solve the problem, because even with enough water, the leaves can still get burnt.
Provide more shade
The main cause of leaf scorch is excessive direct sunlight. As I said above, there are varieties that can tolerate a few hours of direct sunlight, but not everywhere gets the same sun.
In the south, in Hardiness zones 7-8, the sun is stronger than in zones 3 or 4. So even with the same amount of sunlight, hostas will be in different conditions if they are grown in different areas.
If your hostas’ leaves are scorching, then you need to provide them with more shade. If you don’t have enough shady space, cover it with shading netting, which you can find at almost every garden center. I recommend using a netting that reflects at least 50% of the sun’s rays.
You can use four sticks as a frame. Just stick them into the ground around the hosta and put the shading netting on top.
Alternatively, you can use a regular garden umbrella. Place it over the hosta and it will provide shade.
You can remove the shade at the end of the season when the leaves die off and the plant goes into a dormant state.
Read more: Hosta Light Requirements
The previous two tips can only be a temporary solution. If your hostas continue to scorch, it’s best to transplant them into full shade. So, let’s talk a little bit about how to transplant them properly.
The first thing that is important when transplanting is timing. I recommend transplanting in mid-spring or early fall because this is when conditions are best for a change of location.
It is important to transplant the plants 35-40 days before the first frost.
Choose a cloudy morning to transplant your hosta. Try to avoid sunny days. Water the hostas well before transplanting.
The new location should be in full shade or in a place with 2-3 hours of the morning sun but no more.
Dig up the root ball carefully, being careful not to damage any part of the plant. At the new location, dig a hole twice the size of the rhizome to be moved. Fill it with a mixture of garden soil and quality compost (half and half).
Fill the hole with the prepared substrate by 50%. Place the rhizome in the new location so that the stems are not covered with soil. That is, the hosta should grow at the same level as before.
Fill any voids with soil and water with a small amount of water. After a few minutes, the water will run off and the soil will settle a bit. Fill in more soil and water again.
Afterward, keep the soil slightly moist until the plant is rooted. Avoid watering too often. Just check how deep the soil has dried. If it’s more than an inch dry, it’s time to water the hosta.
I also wrote a detailed article on How and when it is best to transplant hostas. If you want to avoid common transplant mistakes, be sure to check it.
Should I cut back scorched hosta leaves?
In most cases, scorched leaves should not be cut back because they can still benefit the plant. Sometimes, however, it is better to remove them. Let’s talk about this in more detail.
Leaves are usually burnt at the tips and edges. As a result, no more than 10-15% of the leaf is damaged. In this case, it is not necessary to cut the leaves.
Throughout the growing season, even partially damaged leaves will be photosynthesized and the plant will get energy from them to grow.
If you cut back all the scorched leaves, the energy will decrease and the plant will grow more slowly. So I don’t recommend cutting it back if the damage is minimal.
However, if the leaves are burnt too much, various diseases can form on the dead tissues in wet weather. In this case, it is better to cut the leaves off completely to avoid problems.
I recommend cutting the leaves and stems 2 inches above the ground. Also, when cutting the stems, be careful not to damage the stub and other stems which should not be cut. Use only sharp and sterile tools when pruning.
How to prevent hosta scorch?
Ignoring the rules of cultivation usually leads to negative consequences. As a result, you will have to correct mistakes and do a lot of extra work. Next, we’ll talk about how to properly grow hostas so they don’t get scorched.
Plant sun-tolerant hostas
There are many varieties of hosta on the market that sellers claim can grow in full sun. However, this is not always the case, so you need to spend more time looking for the right varieties.
In general, many varieties can tolerate sunlight, but their appearance will not be the best. Even if they don’t get burned, their leaves will be pale green-yellow, which is to say, not pretty.
The most sun-resistant varieties include:
- Sum and Substance
- Gold Standard
- Sun Power
- and others.
The fact that some hostas can tolerate the sun does not mean that they can be planted in an open spot where they will receive 10 or more hours of direct sunlight.
Try to plant them so that they are protected from the midday sun and receive no more than 4-5 hours of direct sunlight. For the northern U.S., this may even be a little more (up to 6 hours).
However, for a hardiness zone of 8 or even 7, I don’t recommend planting hostas in direct sunlight at all. If you do, they will be fine for a while, but in dry and hot summers they can get burned.
Lastly, never plant blue hostas in full sun. These varieties require deep shade to produce rich blue color. With a little sun, they will turn pale green.
Read more: Are there any hostas that can take full sun?
The soil should hold water for a while
The next thing you can do to reduce the hosta scorch is to make the soil hold water better.
Suppose your yard has sandy soil or soil that dries out quickly in the summer heat. Add to that direct sunlight, and you get burnt hostas.
To improve the soil, you need to add components that can hold water longer. You can add organic matter (such as compost).
If you choose to add compost, you’ll get another benefit – the soil will be more nutritious for your plants. As a result, you will not have to fertilize them too often.
The amount of compost in the mix can be higher (30-40%). I recommend using good, quality compost, so give it your utmost attention.
Water hostas properly
I already wrote about watering above, but I want to say a few more words about it.
Watering alone will not solve the problem of scorched leaves. However, if you give your hosta enough moisture, the chance of sun damage will be reduced.
The soil around the plant should not dry out more than an inch. However, it should not be constantly wet.
The amount of water will depend on the size of the bush. Miniature and medium-sized varieties will need one gallon of water at a time. The large and giant ones will need two gallons or more.
Timely watering can be quite a hassle, so it’s best to install drip irrigation. Just run a drip hose to each bush, and you’re done.
You can also install an automatic irrigation controller with a rain sensor. Then you don’t have to worry about watering at all. The main thing here is to set the controller correctly to avoid overwatering.
You want to mulch the surface to prevent it from drying out quickly. In the case of hostas, this works very well.
Another advantage of mulch is that the soil underneath doesn’t get too hot. As a result, the plants will be even more comfortable in the summer heat.
The best mulch for hostas is two materials: compost and pine bark.
In addition to its main task, compost will make the soil around the hosta more nutritious. However, this material also has disadvantages.
Firstly, it creates virtually no barrier to weed growth, so you will have to weed the beds from time to time.
Secondly, the lifespan of compost as a mulch is shorter than other types.
The second good mulching material is bark. It lasts the longest. However, it brings almost no nutrients to the soil.
Of course, there are many other mulching materials. If you want to know more about these materials and how to properly mulch hostas, check out my article 4 Best Mulch For Hostas.
Will scorched hostas come back?
A scorched hosta will definitely recover after some time. Of course, the brown leaves won’t turn green anymore, but the next year the hosta will produce new young leaves.
In general, sunburn will not kill the hosta. The worst that can happen is that the hosta will lose some of its leaves, but the rhizome will keep alive.
If you take care of it properly, your hosta will be as good as new next spring.