If You See White Stuff on Your Mulch, This is What it Means

Updated: Mar. 18, 2022

Don't let the icky appearance deceive you—that white stuff on mulch can be beneficial to your landscape.

Who doesn’t love a beautiful, healthy yard? Some may opt for edible landscaping while others focus on the bright hues and fragrances of certain blossoms (like these gorgeous blue flowers). No matter what you grow, it’s important to take the correct steps for proper care.

So when it comes to mulch and compost, all you seasoned gardeners out there know a thing or two. But what’s that white stuff on mulch?

That White Stuff on Mulch Is Slime Mold

Yes, that odd, spongy mass of white spores is actually a slime mold. But a slime mold isn’t actually a fungus in the sense of the word as we understand it. Instead, it’s more like an amoeba and often appears as a giant, icky blob. They don’t really identify as either plant or animal and actually exist to decompose organic matter.

This particular type of slime mold spreads through individual spores. It may not look the prettiest, but it’s beneficial to your organic mulch. The slime mold will actually work to return vital nutrients to your soil! It’s not poisonous or toxic and typically dries up and spreads its spores elsewhere after awhile.

How to Get Rid of Slime Mold

There is no surefire way to prevent slime mold from appearing on your mulch. And, as I mentioned before, it really only works to help instead of hurt. However, if you find the white slime is conflicting with your aesthetic, you can simply bury the mold into the mulch itself.

You can also use a rake to remove the mold and dispose of it somewhere else, or if you’d prefer to wait for it to finish its job, let it dry out to powder and blast it with a hose. Just remember to say thank you for all the hard work it’s doing for your beautiful flowers!

Taste of Home
Originally Published on Taste of Home