What’s the Reason Behind Painting Trees White?

If you’ve ever walked through a park, rural village, or older neighborhood and noticed tree trunks painted white—especially the lower portion—you might wonder why people do this. It may look decorative, but the reason is far more practical and rooted in plant protection.

Below is the explanation behind this common practice—and why it’s more important than it looks.

1. Protects Trees From Sunscald (Winter Burn)

During winter, the sun can heat the bark of a tree, causing the internal tissues to “wake up.” When temperatures suddenly drop at night, the warmed tissues freeze and crack.
This damage is known as sunscald.

Painting the trunk with white latex paint reflects sunlight, helping the bark maintain a more stable temperature. This simple step prevents splitting and protects young trees during harsh winters.

2. Shields Against Pests and Insects

Whitewashing the trunk can discourage many insects from nesting or climbing the tree.
The alkaline mixture—often lime-based—creates an environment that pests dislike, reducing:

• Ants
• Beetles
• Borers
• Fungal spores

This natural protectant has been used for generations, especially before chemical treatments existed.

3. Prevents Disease and Fungal Problems

Some white tree paints include lime or copper sulfate. These ingredients help protect the bark from:

• Fungal infections
• Bacterial growth
• Mold
• Mildew

This is especially important for fruit trees, which are more vulnerable to disease.

4. Protects Young, Thin-Barked Trees

Young trees—and species like citrus, apple, or eucalyptus—have thin bark that burns easily.
The white paint acts like sunscreen, preventing:

• Heat cracks
• Moisture loss
• UV damage

This helps the tree grow healthy and strong during its early years.

5. Helps Prevent Rodent Damage

In cold winters, rodents like rabbits or mice may gnaw on tree bark for food.
The paint mixture makes the bark less appealing, reducing chew damage that could otherwise kill the tree.

What Type of Paint Is Used?

People do not use standard wall paint, which can suffocate the bark.
Instead, the mixture is typically:

A diluted white latex paint

• 1 part white latex paint
• 1 part water

Or a traditional whitewash mixture of:

• Hydrated lime
• Water
• A small amount of salt

This creates a breathable coating that won’t harm the tree.

Why Only the Bottom Half?

Because this is the part most vulnerable to:

• Sun heat during winter
• Rodent attacks
• Insects climbing
• Fungus and moisture exposure
• Mechanical damage (like lawn equipment)

There’s no need to paint the entire trunk.

Final Thoughts

Painting the lower section of a tree white is more than a visual quirk—it’s a time-tested method of protecting trees from harsh weather, pests, and disease.

It’s a simple, inexpensive technique that keeps trees healthier, stronger, and more resilient, especially in regions with extreme temperatures.