How do you deal with sunscald?

Written by: Lars Nyman

How do you deal with sunscald?


Gardening can be an incredibly rewarding pasttime, but when the temperatures start to rise, it can also quickly become quite a challenge. Sunscald is one of the many potential problems gardeners face when summer temperatures are at their peak. Sunscald occurs when an extreme temperature change from hot to cold causes the plant tissues to become damaged. Fortunately, there are a few different ways to both prevent and treat this issue. In this article, we will explore the causes of sunscald and the best practices for preventing and treating this condition.

Cheatsheet: Dealing with Sunscald


β˜€οΈ Provide shade to protect plants from intense sunlight.

πŸ’¦ Mulch soil to retain moisture and prevent rapid temperature changes.

πŸ… Grow sunscald-resistant varieties like 'Heatmaster' tomatoes.


πŸ’§ Water deeply and evenly to maintain soil moisture.

🌱 Increase watering during heatwaves to prevent wilting.

Plant Care

🏑 Prune excessive foliage to improve airflow and prevent heat buildup.

🚿 Use a gentle spray to cool and hydrate sunscalded leaves.


🌽 Harvest fruits and vegetables before they become overripe.

πŸ›’ Consume or process sunscalded produce promptly.

Interesting Facts

🌑️ Sunscald occurs when temperatures exceed 90°F (32°C) during fruit development.

🌿 Healthy plants with balanced nutrition are more resistant to sunscald.

πŸ₯¦ Sunscald can affect a variety of plants, including tomatoes, peppers, and leafy greens.

πŸ’ͺ Proper care reduces sunscald's impact and increases plant resilience.


Understanding Sunscald

As a lifelong gardener, I’ve come across many challenges and setbacks, but none quite as frustrating as sunscald. For those who don’t know, sunscald refers to the result of a plant being exposed to sharp fluctuations in temperature, especially when combined with harsh sunrays. The affected areas bleach into a pale color and may even have a papery texture.

Identifying Sunscald

Being able to identify sunscald is essential. The primary symptom of sunscald is a discoloured, sunken, and often cracked area on the fruit, stem, or leaf of the plant. However, not all pale or discoloured patches are sunscald. Look for signs of a papery texture, peeling skin, and a change in firmness. Most importantly, remember that sunscald primarily affects the side of the plant facing the sun.

Dealing with Sunscald

Once you have identified sunscald, damage control becomes key. Focus on providing shade for your scalded plants. One way to do so is with a shade cloth. If the sunscald is on your tree trunks, paper tree wrap works wonders. Personally, I do a mixture of both, depending on the type of plant.

Not all plants are created equal, and not all plants will require the same type of sunscald prevention. Try multiple methods until you find what works best for your garden.

Preventing Sunscald

In my years of gardening, I've found that prevention is better than cure, especially in the case of sunscald. Young plants, newly transplanted ones, or those recently pruned are most susceptible to sunscald, so it's vital to offer them protection.

Create artificial shade for these susceptible plants. Consider using garden structures like pergolas or trellises, or a shade cloth as I mentioned earlier. These create a barrier between the plant and the sun, reducing the risk of sunscald.

Adapting for winter

Sunscald isn't just a summer problem – it can also be a real headache during winter. This is especially true for trees when the warm winter sun can unexpectedly damage their trunks. Whitewashing the trunks with a solution of half white latex paint and half water has always worked wonders for me.

Be Patient and Diligent

Nature throws curveballs, and sunscald is one of them. However, the key is to stay patient, diligent, and learn from each experience. With appropriate preventative measures and timely intervention, the threat of sunscald can be considerably reduced.


What is sunscald?

Sunscald is a plant condition caused by excessive exposure to intense sunlight.

Which plants are prone to sunscald?

Young or tender plants, especially vegetables and fruits, are more susceptible to sunscald.

What are the signs of sunscald?

Look for bleached or discolored patches on leaves, fruits, or stems.

How can I prevent sunscald?

Protect plants with shade cloth, apply sunscreen spray, or provide natural shade using taller plants or trellises.

Can I treat sunscald once it occurs?

No, sunscald is irreversible, but you can remove affected parts to prevent further damage.

When is sunscald most likely to occur?

Sunscald typically happens during hot and sunny weather, often in late spring or summer.

What other measures can I take to protect my plants?

Water plants thoroughly, avoid over-fertilization, and prune overcrowded branches to improve air circulation.

What if my plants still develop sunscald?

Consider relocating them to a shadier spot or using protective covers during the hottest parts of the day.

Sunscald can be a challenging problem to deal with as a gardener, but it doesn't have to ruin your harvest. With the right tools and techniques, you can keep your plants healthy and thriving in areas that get direct sunlight. Utilizing shade during the hottest times of the day and applying mulch around the base of your plants will help to ensure your hard work pays off with a successful harvest.

Want to know more about Sunscald? Check out these posts:

Further reading:

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