Why Is My Boxwood Turning White

Your boxwood is turning white primarily due to environmental stress, pests, or diseases.
 
This discoloration on the leaves or stems often signals something is off with your plant.
 
Understanding why your boxwood is turning white is the first step to fixing the problem.
 
In this post, we’ll explore the common reasons behind boxwood turning white and how to treat it.
 
Let’s get straight into the causes.
 

Why Is My Boxwood Turning White?

The most common reasons your boxwood is turning white include sunscald, fungal infections, and pest damage.
 
Let’s look at each cause in detail.
 

1. Sunscald and Winter Burn

Boxwood turning white often happens after harsh sun exposure on cold winter days.
 
When the ground is frozen, roots can’t absorb water, so leaves lose moisture faster than they can replace it.
 
This leads to dry, bleached patches that look white or straw-colored.
 
South or west-facing sides of the plant are most affected because they get the strongest afternoon sun.
 
If your boxwood is turning white only on one side, sunscald or winter burn is likely the cause.
 

2. Fungal Diseases Like Boxwood Blight

Boxwood blight (Calonectria pseudonaviculata) is a serious disease that makes boxwood turn white rapidly.
 
You’ll notice dark spots on leaves that then fade to a light tan or white as the leaf dies.
 
Black streaks may also appear on stems, and leaves drop off quickly.
 
This fungal infection spreads through splashing water and contaminated tools.
 
If you see these symptoms, your boxwood turning white could be blight, and quick action is needed.
 
Another fungal issue is Volutella canker, which causes white to pinkish spore masses on stems.
 
But the main sign is dieback combined with a whitish coating.
 

3. Pest Infestations

Certain bugs can make your boxwood turn white by sucking out leaf sap.
 
Boxwood spider mites cause stippling that gives leaves a pale, whitish appearance.
 
Boxwood psyllids also cause cupped leaves with a whitish residue from their waxy secretions.
 
Scale insects leave behind white or light-colored waxy shells that look like tiny bumps on stems and leaves.
 
If you inspect closely and see tiny moving specks or sticky honeydew, pests are why your boxwood is turning white.
 

4. Nutrient Deficiencies

A lack of key nutrients like iron or magnesium can make new growth on boxwood turn white or pale yellow.
 
Iron chlorosis often starts on the youngest leaves, turning them white while veins stay green.
 
Soil pH that’s too high (alkaline) locks up iron even if it’s present in the soil.
 
If your boxwood is turning white on the newest leaves but older leaves are fine, suspect a nutrient problem.
 

How to Diagnose Boxwood Turning White

You can figure out why your boxwood is turning white by looking closely at the patterns and symptoms.
 

Check the Location of the White Areas

If the white appears only on the side facing the sun, it’s likely sunscald or winter burn.
 
If white is scattered throughout the whole plant, fungal or pest issues are more probable.
 

Inspect Leaves and Stems for Spots or Bugs

Use a magnifying glass to look for tiny mites, scales, or fungal spores on boxwood turning white.
 
Black streaks on stems point to blight, while sticky residue suggests pests.
 

Test the Soil pH and Nutrient Levels

A simple soil test from your local extension office can reveal if your boxwood is turning white due to deficiency.
 
Boxwood prefers a pH between 6.5 and 7.0 for optimal nutrient uptake.
 

Treatments for Boxwood Turning White

Once you know the cause, you can treat your boxwood and help it recover.
 

1. For Sunscald or Winter Burn

Prune back dead, white branches in early spring after new growth starts.
 
Mulch around the base to keep soil temperature stable and protect roots.
 
Apply an anti-desiccant spray in late fall to reduce moisture loss from leaves.
 

2. For Fungal Diseases

Remove and destroy infected leaves and branches immediately to stop spread.
 
Avoid overhead watering because splash spreads spores that make boxwood turn white.
 
Apply a fungicide labeled for boxwood blight (like chlorothalonil or tebuconazole) according to instructions.
 
Sanitize pruning tools between cuts to avoid reinfecting healthy parts of your boxwood turning white.
 

3. For Pests

Hose off spider mites with a strong stream of water to reduce their numbers.
 
Use horticultural oil or insecticidal soap to control scales and psyllids on boxwood turning white.
 
Repeat treatments every 7–10 days as needed until the infestation clears.
 

4. For Nutrient Deficiencies

Apply a balanced slow-release fertilizer formulated for evergreens.
 
If iron is lacking, use chelated iron supplements or soil acidifiers to correct pH.
 
Water deeply after fertilizing to help nutrients reach the roots of your boxwood that is turning white.
 

So, Why Is My Boxwood Turning White?

Your boxwood is turning white because of one or more factors like sun damage, disease, pests, or poor nutrition.
 
Diagnosing the exact cause requires careful observation of leaf patterns, stem symptoms, and growing conditions.
 
Once you identify why your boxwood is turning white, you can take the right treatment steps to restore its health.
 
With proper care and prompt action, your boxwood can bounce back and stay green again.