The Art of Whitewashing Your Fruit Trees

Whitewashing (or limewashing) fruit trees is an age-old gardening practice that combines practicality with tradition. Whether to protect trees, enhance their health, or add a decorative touch, whitewashing remains a low-cost, eco-friendly, and effective solution.

Here’s everything you need to know about whitewashing and why it’s worth adding to your gardening routine.

Jump to:

What is Whitewashing?
Benefits of Whitewashing Fruit Trees
How to Make and Apply Whitewash
Basic Limewash Recipe
Tips for Success
Other Types of Lime Mixture for Trees
Additional Uses for Whitewash
The Science Behind Whitewash Durability
Conclusion

What is Whitewashing?

Whitewashing orchard trees — Whitewashing trees has been a part of tree and orchard care for centuries.

Slaked line (i.e., calcium hydroxide) is the main ingredient used in whitewash. It’s safe for human consumption (it’s used to preserve eggs), inhibits the growth of moss, works as a kind of antimicrobial, and has other useful properties.

Whitewashing, or limewashing, involves applying a mixture of slaked lime (calcium hydroxide) and water to tree trunks and sometimes large branches in order to protect them. Historically, it has also been used to paint homes, barns, fences, and many other structures. It’s non-toxic, environmentally friendly, protects plants from heat and insects, and, best of all, it’s cheap! (That’s my favorite word.)

Whitewash is also aesthetically pleasing because it glows in the sun – the countless microscopic crystals in lime gives it that amazing gleam.

Benefits of Whitewashing Fruit Trees

A farmer brushes whitewash onto a fruit tree to protect against harsh sunlight and to slow down blooming in early spring.

What are the benefits of whitewashing? Let me count the ways.

Prevent Bark Splits: In winter, tree trunks often experience temperature fluctuations. Sunlight warms one side of the trunk while the other remains cold, causing the bark to expand unevenly and potentially rupture. A coat of whitewash reflects the sunlight and keeps the trunk from heating up.
Delay Blossoming: Whitewashing can delay the blossoms in early spring by about a week. This gets them out of the range of spring freezes that can kill tender blossoms.
Pest and Disease Resistance: Lime is alkaline, so it can act as an antimicrobial and reduce bacteria, fungi, and insects on the trunk.
Protip: Adding a small amount of copper salts, like copper oxychloride, boosts its effectiveness against microbes. Bordeaux mixture is lime mixed with a larger amount of copper. This turns a very attractive shade of blue, and it’s often sprayed on grapevines to curb fungal diseases like downy mildew. However, in the case of whitewashing trees, add just enough copper to turn the mixture a faint blue – no more than that. It will dry to white when painted on the trees.
Prevents Sunburn: This applies to climates with lots of snow as well as balmy areas with lots of sun and any place in between. If the trunk isn’t protected by leaves, slap some whitewash on there. Sunscald can also ruin a fruit tree’s trunk and branches that are exposed to a lot of sun – even if the sunlight is indirect, from being reflected from the snow.
Decoration: Not only are whitewashed trees functional, but they’re decorative. A row of pretty little trees with white trunks looks charming.

How to Make and Apply Whitewash

Whitewashed tree trunks on hardwood trees — Very fancy! Remember that whitewashing trees can transform them into a decorative part of your landscape as well.

Not all lime is created equal. Calcium hydroxide, commonly known as slaked lime or hydrated lime, is the best lime to use for whitewashing. Calcium hydroxide dissolves quickly in water and works well on trees and many other surfaces. Though there’s a warning label on the bag, fear not. Its high alkalinity can burn from prolonged contact when it’s wet. It’s safe when it dries. It dries quickly, and once it reacts with the oxygen in the air, the lime becomes inert – harmless. That’s why you can sit on a rock or lean on a fence that’s been limewashed and not get chemically burned.

The other type of lime is calcium carbonate, sometimes called common garden lime or agricultural limestone. This type of lime works best as a soil additive to “sweeten” the soil and make it more alkaline. However, calcium carbonate does not dissolve well in water, so you’ll end up wasting a lot of time stirring. Instead, add it to the soil around your clematis or your tomatoes.

Basic Limewash Recipe

Mixing lime whitewash for trees — Limewash should be about the consistency of skim milk. No need to make it too thick.

Gather these things before you start:

Slaked lime, aka calcium hydroxide
Water
(Optional) A little package of copper salts
5-gallon bucket
A stirring stick
Water-resistant gloves (be a safety-first gardener)
Big ol’ paintbrush

Ingredients:

1 part slaked lime (aka calcium hydroxide)
6–8 parts water

Optional: Up to 0.5% copper salts (e.g., 40 grams of copper oxychloride per 15 liters of whitewash)

Steps:

Mix the lime and water to achieve a consistency similar to skim milk.
Let the mixture rest overnight.
Stir thoroughly before use.
Apply a thin, even coat to the tree trunks and large branches. Avoid layering too thickly, as this can lead to flaking. You can put on a few coats, though, with no issues.

Tips for Success

Brushing whitewash on fruit trees — A woman applies whitewash to a fruit tree with a brush.

Here are a few tricks of the trade.

Safety First: When handling limewash, wear gloves to prevent irritation. Once diluted and cured, whitewash is safe.
Application Timing: Choose warm, dry weather for application to make sure the whitewash dries well. Avoid applying late in the day to prevent morning dew won’t interfere with drying. Obviously, don’t apply this in a rainstorm.
Don’t Overdo It: Stick to a thin, single coat. Thick applications may turn into plaster and require more substrate for durability.

Other Types of Lime Mixture for Trees

Whitewashed cherry trees — Cherry trees in early spring are treated with Bordeaux mixture to combat mildew.

Bordeaux mixture is a variation of limewashing trees used since the 1860s. For this, copper sulfate is mixed with lime and water. The resulting wash is often light blue or green. Copper adds additional protection against fungus and is often used to that effect in vineyards and orchards.

Additional Uses for Whitewash

Mixing white wash — Construction bucket with lime on construction site.

Whitewash isn’t just for trees! You can use it to coat:

Barns and sheds for a rustic look.
Chicken coops and animal shelters to reduce heat and improve sanitation.
Concrete walls to protect against sun damage and algae growth.
Stones along a path so they show up better at night, allowing you to walk without a flashlight.
Fences, so they look excellent. (Bonus points if you can talk your friends into doing the work for you as Tom Sawyer did).

The Science Behind Whitewash Durability

After application, the limewash reacts with carbon dioxide in the air as it dries, turning back into limestone again. This makes it incredibly durable and inert. Limewash on trees is safe, long-lasting, and even re-sequesters carbon lost during its production. (Only a little bit, but something’s better than nothing.)

Conclusion

Treating cherry trees in early spring with whitewash — Cherry trees in early spring are treated with Bordeaux mixture to combat mildew. Bordeaux is a variation of limewashing, and it also protects against blight and other diseases in plants.

Whitewashing is a simple yet effective way to protect your fruit trees and make them look really cool. A bit of care and patience helps your trees thrive while adding charm to your garden. It’s a useful practice that shouldn’t be allowed to die out. You’ll like the results, and your trees will thank you later.