How To Tell If Blueberries Have Worms

Blueberries have worms if you spot tiny white larvae inside the fruit, especially near the stem end where they burrow in.
 
These worms are usually the larvae of the blueberry maggot fly or the spotted wing drosophila, both of which love to lay eggs in ripe berries.
 
So if you’ve been wondering how to tell if blueberries have worms, you’re in the right place.
 
You can tell if blueberries have worms by looking for small entry holes, soft spots, or fruit that sinks in water when other berries float.
 
In this post, we’ll go over the signs that blueberries have worms, how to check for them, and what to do if you find them.
 
Let’s get into it.
 

How to Tell if Blueberries Have Worms

Learning how to tell if blueberries have worms comes down to a few simple checks you can do at home before eating or freezing your harvest.
 
Here are the main signs that blueberries have worms.
 

1. Tiny Entry Holes on the Surface

One of the clearest signs that blueberries have worms is a small, pin-sized hole on the skin.
 
This is where the adult fly laid its egg, and it’s often near the stem or on the side of the berry.
 
If you look closely at your blueberries, you might notice these holes along with a slight dimple or bruise around them.
 
When blueberries have worms, the hole is usually the first clue you’ll spot before anything else.
 

2. Soft, Mushy, or Shriveled Spots

Worms feed on the inside of the berry, which causes the flesh to break down and turn mushy.
 
If blueberries have worms, you’ll often feel a soft or squishy spot when you gently squeeze them.
 
Healthy blueberries should feel firm and plump, so any berry that feels unusually soft is worth a closer look.
 
Over time, infested blueberries may also shrivel or leak juice, which makes them easier to pick out from the rest.
 

3. The Saltwater Test

The easiest way to tell if blueberries have worms is to soak them in saltwater.
 
Mix about one cup of salt into a gallon of water, then drop your blueberries in and wait 15 to 30 minutes.
 
If blueberries have worms, the larvae will crawl out of the fruit and float to the surface or sink to the bottom of the bowl.
 
This test is a favorite among home gardeners because it forces even the tiniest worms to reveal themselves.
 
Just rinse the berries well afterward, and they’re still safe to eat or freeze.
 

4. Discolored or Sunken Areas

Blueberries that have worms often develop discolored patches that look darker or more purple than the rest of the skin.
 
These spots appear because the larvae are feeding inside, damaging the tissue and causing it to break down.
 
You may also notice that blueberries with worms look sunken or wrinkled compared to the smooth, shiny surface of healthy berries.
 
When you’re sorting through a batch, set aside any berry with odd coloring or a collapsed look.
 

Why Blueberries Get Worms in the First Place

Understanding why blueberries have worms makes it easier to prevent them in the future.
 
Here’s what’s usually going on.
 

1. Fruit Flies Lay Eggs on Ripe Berries

The spotted wing drosophila and blueberry maggot fly both target soft, ripe fruit.
 
They pierce the skin and lay eggs inside, and within a few days, those eggs hatch into tiny worms.
 
That’s why blueberries have worms more often during warm, humid weather when these flies are most active.
 

2. Overripe Fruit Attracts More Pests

The longer blueberries stay on the bush, the more likely they are to attract egg-laying flies.
 
Blueberries that have worms are usually the ripest ones, since the flies prefer fruit that’s already soft and sweet.
 
Picking your berries as soon as they’re ripe helps cut down on the chances that blueberries have worms.
 

3. Poor Storage Makes It Worse

If you leave fresh blueberries sitting out at room temperature, any eggs already inside can hatch faster.
 
Refrigerating them soon after picking slows this down and keeps worms from multiplying.
 
So if you’re worried that blueberries have worms, get them into the fridge or freezer quickly.
 

What to Do if Your Blueberries Have Worms

If you’ve confirmed that blueberries have worms, don’t panic.
 
First, soak the berries in saltwater to flush out the larvae, then rinse them thoroughly under cold running water.
 
Next, check each berry by hand and toss any that are mushy, discolored, or still show signs of damage.
 
You can still eat the good ones fresh, bake them into muffins, or freeze them for smoothies later.
 
And honestly, a few extra grams of protein never hurt anybody.
 

So, How to Tell if Blueberries Have Worms?

You can tell if blueberries have worms by checking for tiny entry holes, soft spots, discoloration, and by doing the saltwater test.
 
Blueberries have worms when fruit flies lay eggs inside ripe berries, and the larvae grow by feeding on the flesh.
 
The good news is that these worms are harmless to humans, and a simple saltwater soak removes them easily.
 
Now that you know how to tell if blueberries have worms, you can enjoy your harvest with confidence.