Sun Scorch in Plants: How to Spot and Prevent It

Few things make a gardener happier than sunshine, but too much of it can sometimes spell trouble for our plants. Sun scorch (also called sunburn) is a common issue in greenhouses and gardens during hot spells, leaving plants looking stressed and damaged. Let’s explore what sun scorch is, how to recognise it, and what you can do to protect your crops.

What Is Sun Scorch?

Sun scorch occurs when intense sunlight and heat overwhelm a plant’s natural defences. The leaves and fruit can’t cool themselves quickly enough, leading to cells drying out and dying. This often happens when plants are already stressed by lack of water, poor airflow, or sudden exposure to strong sun after cloudy days.

Symptoms of Sun Scorch

The signs are usually very distinct and appear rapidly during heatwaves or after moving plants outdoors. Look out for:

• White or pale yellow patches on leaves, especially the upper surfaces facing the sun.
  
• Papery, dry areas on leaves that look thin and brittle.
  
• Pale blotches on fruit, particularly tomatoes, peppers, and cucumbers, where the skin looks bleached and leathery.

These symptoms are often mistaken for disease, but unlike fungal problems, sun scorch doesn’t spread.

Commonly Affected Plants

While many crops can be hit, sun scorch is especially common in:

• Tomatoes – fruit may show pale, dry, sunken patches.
  
• Cucumbers – leaves often develop bleached, papery spots.
  
• Peppers – foliage and fruit can both suffer sunburn.

Plants grown in greenhouses are particularly vulnerable due to the extra heat and lack of shading.

How to Prevent Sun Scorch

The best way to deal with sun scorch is prevention. Here’s how you can protect your plants:

• Provide shade – use shade cloth, fleece, or netting during the hottest part of the day.
  
• Water consistently – keep soil moist, as well-hydrated plants cope with heat better.
  
• Harden off plants gradually – when moving seedlings outside, introduce them to direct sunlight over a week or two.
  
• Maintain good airflow – in greenhouses, open vents and doors to prevent overheating.

Can Plants Recover from Sun Scorch?

Once the white, papery patches appear, the damaged tissue won’t recover. However, as long as the plant is otherwise healthy, it can grow new leaves and continue producing fruit. Simply remove badly affected foliage to reduce stress and keep the plant thriving.

Sun scorch may look alarming, but it’s rarely fatal. By spotting the symptoms early and giving your plants a little extra protection, you can prevent lasting damage and keep your summer crops growing strong.