Hey garden friends! Have you ever been working in your garden and suddenly noticed some weird, bright orange stringy things growing through your mulch? I totally get it – these mysterious orange roots can be pretty freaky when you first spot them! As a passionate gardener I’ve dealt with this situation many times so let me break down everything you need to know about those funky orange growths.
What Are Those Orange Things in My Mulch?
Those bright orange “roots” you’re seeing usually aren’t actually roots at all! Most often, what you’re looking at is a fascinating organism called slime mold I know, sounds gross right? But stick with me here – these weird little creatures are actually pretty cool.
Meet the Slime Mold Family
- Slime molds are unique organisms that are neither plant nor animal
- Two common types you’ll find in mulch:
- Fuligo septica
- Physarum polycephalum
- They can appear in various colors:
- Bright orange (most common)
- Yellow
- Tan
- Brown
- Grey
Should I Freak Out About Slime Molds?
Short answer: Nope! These strange orange fellows are totally harmless to your plants. In fact, they’re actually helping your garden! Here’s why:
- They break down organic matter
- Release nutrients (especially nitrogen) into your soil
- Help with natural decomposition
- Only stick around for a few weeks
Getting Rid of Orange Slime Molds (If You Really Want To)
While these organisms are beneficial, I get that some folks just don’t want them in their garden. If that’s you, here are some ways to manage them
Quick Fix Methods:
- Rake up affected mulch
- Turn/stir mulch regularly
- Improve air circulation
- Water early in the day
- Add agricultural lime
When Should You Actually Worry?
While orange slime molds are harmless, there are some other mulch-dwelling organisms you should watch out for:
Red Flag Organisms:
- Mushroom clusters (sign of excess moisture)
- Leaf spots/blight
- Root rot
- Termites
- Aggressive weeds
- Rodent activity
Pro Tips for Choosing the Right Mulch
We’ve learned a lot about mulch maintenance over the years at Stone Post Gardens. Here’s what really matters:
Mulch Selection Checklist:
- Choose between organic or inorganic
- Check particle size (coarser is better)
- Verify source material quality
- Maintain proper depth (2-3 inches ideal)
- Plan annual replacement
Real Talk: Other Orange Root Mysteries
Sometimes those orange things in your mulch might actually be roots! We’ve seen cases where:
- Tree roots searching for water (can spread 3-4x the canopy size!)
- Oriental bittersweet roots (invasive plant)
- Various fungal networks
Our Stone Post Gardens Pro Tips
- Don’t panic when you see orange growth
- Monitor moisture levels in your mulch
- Maintain good air circulation
- Replace mulch annually
- Keep yard waste away from mulch beds
Final Thoughts
Listen, I know those bright orange growths can look super weird and maybe even scary at first. But 99% of the time, they’re just harmless slime molds doing their thing to help your garden thrive. Just keep an eye on moisture levels, maintain good airflow, and you’ll be golden!
Need more gardening advice? Drop by Stone Post Gardens or hit us up with your questions. We’re always happy to help fellow garden enthusiasts keep their beds looking fresh and healthy!
Remember, a little weird orange stuff in your mulch just means your garden is alive and thriving. Happy gardening, friends!
Got questions about your garden? Visit us at Stone Post Gardens – 1185 Randolph Road, Middletown, Connecticut, or give us a call at 860.343.0360. We’re here Monday-Friday 9am-6pm and weekends 9am-5pm!
Harmless orange slime mold found in gardens
MISSISSIPPI STATE — Many gardeners across the state are shocked by sprawling, bright orange masses that appear quickly in gardens, but this scary looking fungus is quite harmless.
Clarissa Balbalian, plant diagnostic lab manager with the Mississippi State University Extension Service, said the fungus is a slime mold that feeds on decaying woody material.
“It doesnt hurt plants or people,” Balbalian said. “Slime molds live on fungi, bacteria and other microscopic creatures that decay organic material.”
Balbalian said this fungus is usually found on the ground and looks like orange dog vomit. It is lumpy and flat, and its color can range from pink to red or orange. It starts out moist, but dries to form a hard crust as it matures. Inside are dark black, powdery spores.
“It typically likes a bit of moisture, so it is common to see it in areas that are irrigated,” Balbalian said. “In Mississippi, we could have it all the time, but it is less common in cooler weather.”
She said this slime mold will dry up and disappear in time, but can be picked up and discarded. Try not to break the mass open to prevent the further spread of spores.
Balbalian said this mold is common in mulch and any kind of dead, organic matter. Many people find it in their flower or shrub beds that have been mulched.
“There is nothing you can do to prevent getting it other than not have wood mulch or any dead organic materials around,” Balbalian said. “There is no spray you can use to kill it, and the best way to get rid of it is to use a shovel to lift it and throw it away.”
Norman Winter, Extension horticulturist, said despite the possibility that it will host mold, mulch serves a valuable purpose in landscapes.
“Mulch prevents the loss of moisture through evaporation, and it also helps prevent weeds, which compete for the nutrients and water youre trying to get to the plants you want to grow,” Winter said. “By preserving moisture, youre preventing cracks that can lead to shifting foundations and other problems.”
Balbalian said another type of slime mold forms gray balls on grass blades that are wet for extended periods. This mold feeds on decaying organic matter and does not harm the grass, but simply uses the blades for support.
As manager of the MSU Plant Pathology and Nematology Lab, Balbalian sees these kinds of fungus and many other microorganisms and parasites that attack Mississippi plants. Last year, the lab analyzed about 700 disease samples and tested about 1,700 samples for nematodes.
The lab serves large-scale farmers, commercial growers and homeowners with plant problems. It is the diagnostic lab for the Mississippi Department of Agriculture and is part of the Southern Plant Diagnostic Network that monitors disease that may pose a threat to agriculture.
Contact: Clarissa Balbalian, (662) 325-2146
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FAQ
What is orange fungus in mulch?
The orange fungus in mulch is scientifically known as Mutinus elegans, and it is usually characterized by an unpleasant smell and a phallic shape. Most of the time, the orange fungus in mulch appears orange in color, but it can sometimes be yellow. This substance is also referred to as slime mold, dog vomit fungus or stinkhorn.
Why does my mulch smell like orange fungus?
The bad odor of the orange fungus in mulch causes it to attract insects such as flies, which are then trapped by the slime the moment they come into contact with it. Sometimes, the orange fungus that grows in your mulch could be Physarum polycephalum. This is also a slime mold and it feeds off vegetation.
How do you remove orange fungus from mulch?
Using a garden hose is ideal for this purpose. You can even manually remove the orange fungus by breaking down the mass of the slime mold into smaller pieces using a shovel. You can then rake it and remove it from the rest of the mulch. Take note that the orange mold will hold on tight to substrates, making it difficult to remove.
What fungus grows in mulch?
There are several species of fungus that home gardeners commonly see growing in mulch, though not all pose a threat. While some fungus is less than noticeable, many gardeners find bright orange patches growing on their mulch. These patches are often a type of slime mold known as Physarum polycephalum.
Can yellow fungi grow in mulch?
Yellow fungi growing in mulch are just as common a problem for gardeners as orange fungus, and it’s often caused by a similar issue. Certain species of slime mold are bright yellow to gold in appearance, which can ruin the look of a perfectly manicured flower bed. Fortunately, most yellow fungi are also harmless to you and your garden.
How do you get rid of orange fungus in flower beds?
When you discover the orange fungus in flower beds that are covered in mulch, assess the situation before you promptly replace the mulch. If the problem is minor, regularly separate the mulch, throw away some of it and retain the lower layer. Add a new mulch on top of the existing one to help you control the fungus.