What’s That Green Stuff at the Beach? It’s June Grass!

June grass algae bloom in the Gulf of Mexico

[Disclaimer: Finding Mandee is reader-supported, if you purchase through links on my site I may earn an affiliate commission at no additional cost to you. As an Amazon Associate, I earn from qualifying purchases.]

“Eww, what’s that green stuff?”

I heard this question countless times growing up on the beaches of Northwest Florida, and the answer is, “It’s June Grass!”

Yes, it’s gross.

It gets in your hair and swimsuit. It makes the normally crystal clear Emerald Coast waters impossible to see through, and it smells funky when it washes ashore.

Tourists and locals alike despise June Grass or ‘seaweed’ season.

It’s certainly not my favorite time of year to go for a salty swim, and I always feel bad for the people who traveled hundreds of miles to experience the Panhandle’s beautiful beaches only to find them filled with slimy green grass.

But what really is it?

June grass in the water along the beaches of 30A
(Not only are there visible chunks, but the dark green of the water means that June Grass is floating all throughout the water.)

What Is June Grass?

Technically, June Grass isn’t really grass at all. It’s algae.

This Cladophora algae bloom happens every year. And though we find it gross, stinky, and slimy, it’s an essential part of the ecosystem.

June grass algae bloom in the Gulf of Mexico
(When the water is dark along the shoreline, there is June Grass!)

How Can I Avoid June Grass?

June Grass tends to start blooming in June, hence the name. However, it can bloom anytime throughout the summer from May to October. In my personal experience, it gets worse in July as the summer gets hotter.

There’s no exact timeline for when it will come and go, but if the water temperature is warm, you can bet you’ll find it somewhere along the Gulf Coast.

The algae also tends to be thicker in areas near freshwater inlets, such as dune lakes and bays. And some locals swear that it’s worse in the afternoons as the tide comes in. So, maybe try to take your swims in the morning.

If you can, try to plan your vacation before water temperatures rise or after they cool. (Which doesn’t mean that it will be too cold to swim.) We have had beach days as early as the end of March and as late as the end of October.

There’s no guarantee that you will avoid the slimy green grass. However, there is a website where people submit June Grass reports, complete with a ‘Grossness Index’ so that you can see what conditions are like before you go.

I took both of these pictures of Lainey at the beach in June of two different years and the water was TOTALLY different! You really never know when it’s going to bloom.

BUT all of my beach pictures from April and May have been beautiful, so if you can plan your visit during those months, I recommend it.

Is It Safe?


Unlike Red Tide, an algae bloom that kills marine animals. June Grass feeds and serves as a breeding ground for marine life.

June Grass is completely safe for both humans and pets, unlike blue-green algae that can be found in freshwater lakes during the hot months.

Some folks complain that it makes them itchy. And I’ve experienced that myself. It’s usually not an issue while I’m in the water, but after I get out and the seaweed starts to dry out and stick to my skin. It stops itching as soon as I rinse it off in fresh water. Thankfully, there’s never any rash or sign that it had been there at all.

So, even if the water is green during your vacation, you can swim as much as you like, knowing that it is completely safe.

girl swimming at beaches of 30a while there is June grass in the water
(The June grass isn’t always super thick, but as you can see here, it is still obvious and visible.)

And if you want to avoid seaweed completely, then check out these 3 springs in Northwest Florida!

2 thoughts on “What’s That Green Stuff at the Beach? It’s June Grass!

  1. You can thank Monsanto and it’s toxic Round up that runs off crops into the ocean for this disgusting “june sludge”…..it is NOT natural. They are lying to you. I started going to the beaches of the panhandle at age 3 in the 1960s and went every year, sometimes twice a year and NEVER saw “june grass” at the beach until around 2005 or so. Also there was a LOT more life on the beaches back then, it was teeming with all kinds of beautiful clams, etc. Not so much nowadays. I wish people would learn to think for themselves and stop parroting the disinformation put out by these wealthy corporate psychopaths.

    1. I was on those same beaches in the 90s and there was June grass then. Admittedly, it wasn’t as thick as it is now, which I would assume is due to more agricultural runoff of fertilizers. But if you go to the beach and look at it in person, it’s clearly algae…not sludge as you say. We see the same thing in our ponds, which have no fertilizer runoff that I’m aware of.

Leave a Reply

Your email address will not be published. Required fields are marked *