Why Do My Blackberries Have White Spots

Your blackberries have white spots because of a fungal issue called white drupelet disorder, which is surprisingly common and not usually dangerous.
 
If you’ve been wondering, “why do my blackberries have white spots,” you’re not alone.
 
This is a question so many home gardeners ask when they notice those pale, tan, or whitish patches on their otherwise perfect-looking berries.
 
The good news is that in most cases, the blackberries with white spots are still perfectly safe to eat.
 
In this post, we’ll take a closer look at why your blackberries have white spots, what causes it, and what you can do about it.
 
Let’s dig in.
 

Why Do My Blackberries Have White Spots?

Your blackberries have white spots due to a few possible reasons, and understanding each one will help you figure out exactly what’s happening in your garden.
 
Here are the main culprits behind blackberries with white spots.
 

1. White Drupelet Disorder

The most common reason your blackberries have white spots is a condition called white drupelet disorder.
 
A blackberry is made up of tiny individual sections called drupelets, and each one usually ripens to a deep, dark color.
 
But sometimes, a few drupelets fail to develop their normal pigment, leaving them pale, tan, or white.
 
This is why you’ll often see blackberries with white spots scattered across just part of the berry surface.
 
White drupelet disorder is not a disease, so it won’t spread from berry to berry like an infection would.
 

2. Sunscald and Heat Stress

Another big reason your blackberries have white spots is sunscald.
 
When blackberries are exposed to intense sunlight and high temperatures, the drupelets on the sun-facing side can get scorched.
 
This heat stress damages the pigment-producing cells, so those sections stay white or tan instead of turning black.
 
If the white spots on your blackberries always seem to be on one side of the fruit, sunscald is likely the cause.
 
This is especially common during sudden heat waves or when plants lose their leaf cover.
 

3. Ultraviolet Light Damage

Ultraviolet light plays a huge role in why blackberries have white spots too.
 
Even on days that don’t feel scorching, strong UV rays can break down the anthocyanins that give blackberries their dark color.
 
When that happens, the affected drupelets can’t complete their ripening process properly.
 
The result?
 
Blackberries with white spots that look a little bleached or faded.
 
This type of damage tends to show up on berries growing at the top of the canopy where UV exposure is highest.
 

4. Poor Pollination

Poor pollination is another reason you might find blackberries with white spots.
 
Each drupelet needs to be pollinated individually, and if some don’t receive enough pollen, they won’t develop fully.
 
Those underdeveloped drupelets often stay small, hard, and pale, creating the white spots you’re seeing.
 
If your blackberries have white spots along with tiny, shriveled sections, pollination problems could be the issue.
 
Cold, wet weather during bloom time often leads to this kind of uneven pollination.
 

5. Spotted Wing Drosophila Damage

Sometimes the white spots on blackberries come from spotted wing drosophila, a tiny fruit fly that lays eggs inside ripening berries.
 
When the larvae feed inside, the surrounding drupelets can become discolored and soft.
 
If your blackberries have white spots that look mushy or sunken, this pest might be the culprit.
 
Check for tiny puncture holes or small larvae near the affected areas to confirm.
 

Are Blackberries With White Spots Safe to Eat?

Blackberries with white spots are generally safe to eat as long as the white areas are firm and the berry smells fresh.
 
White drupelet disorder, sunscald, and UV damage are cosmetic problems, not safety issues.
 
Even the underdeveloped drupelets from poor pollination won’t harm you, though they may taste a bit tart or bland.
 
However, if the white spots are mushy, leaking, or accompanied by a foul smell, toss those berries out.
 
That’s usually a sign of pest damage or spoilage rather than simple white drupelet disorder.
 
When in doubt, it’s always better to compost suspicious berries than risk eating something spoiled.
 

How to Prevent White Spots on Blackberries

You can prevent white spots on blackberries by managing shade, water, and airflow around your plants.
 
Here are the best strategies to keep your harvest looking dark and delicious.
 

1. Provide Afternoon Shade

Since sunscald and UV damage are top reasons blackberries have white spots, giving your plants some afternoon shade helps a lot.
 
A shade cloth or strategic placement near taller plants can block the harshest rays.
 
This is especially important during heat waves when temperatures spike quickly.
 

2. Water Consistently

Consistent watering keeps blackberry plants stress-free, which reduces the likelihood of white spots appearing.
 
Aim for about an inch of water per week, either from rain or irrigation.
 
Mulching around the base helps retain moisture and keeps roots cool during hot spells.
 

3. Encourage Good Pollination

To avoid blackberries with white spots from poor pollination, plant flowers nearby that attract bees and other pollinators.
 
Avoid spraying insecticides during bloom time, since that drives pollinators away.
 
Healthy bee activity means every drupelet gets the pollen it needs to develop fully.
 

4. Monitor for Pests

Keep an eye out for spotted wing drosophila by checking ripe berries regularly.
 
Harvest frequently and remove any overripe or fallen fruit that could attract these pests.
 
Fine mesh netting over your plants can also keep the flies from reaching your blackberries in the first place.
 

So, Why Do My Blackberries Have White Spots?

Your blackberries have white spots most often because of white drupelet disorder, sunscald, UV damage, poor pollination, or spotted wing drosophila.
 
The good news is that most of these causes are cosmetic and won’t harm you, so you can still enjoy your harvest.
 
By providing shade, watering consistently, supporting pollinators, and watching for pests, you can reduce how many blackberries with white spots show up next season.
 
Now that you know why your blackberries have white spots, you can pick with confidence and enjoy the sweet ones.