What Is the Red, Smelly Thing Growing in My Backyard? The Surprising Truth About Stinkhorn Mushrooms

 

Have you ever stepped into your yard one morning and spotted something bright red-orange sticking up from the mulch?Identify Plants

At first glance, it might look like a strange little alien, a piece of coral, or something that definitely doesn't belong in an ordinary garden.

And then you get closer.

That's when you notice the smell.

If you've discovered a bright red-orange fungus that appeared almost overnight, you may be looking at a red stinkhorn mushroom. These unusual fungi are known for their distinctive shapes, surprisingly rapid appearance, and an odor that can be downright unpleasant. Some resemble slender red fingers, while others look like tiny horns or strange, spongy structures.

But here's the interesting part: while stinkhorns can look alarming, they're often simply doing what fungi do best—breaking down organic material and spreading their spores.

Still, identifying the exact species from a quick backyard glance isn't always easy. And when someone says a mushroom is "safe," it's important to understand what that actually means.

Let's take a closer look at how to recognize a red stinkhorn, why it smells so bad, and what you should do if one appears in your yard.Source Farm Gear

What Is a Red Stinkhorn Mushroom?

A red stinkhorn is a type of fungus belonging to a group commonly known as stinkhorns. Several species, including members of the genus Mutinus, have slender, upright fruiting bodies that range from reddish-orange to pink or coral.

Unlike the familiar cap-and-stem mushrooms you might see growing in a lawn, stinkhorns often have unusual shapes. Some resemble narrow fingers, pointed horns, or elongated sponges.

They may appear in garden mulch, compost, leaf litter, decaying wood, or other places where organic material is breaking down.

According to the University of Florida's Institute of Food and Agricultural Sciences, stinkhorns are particularly associated with decomposing wood and plant material. Their unusual appearance and strong smell are part of a natural process that helps them reproduce. Source: University of Florida IFAS Extension

Why do they appear so suddenly?

One of the strangest things about stinkhorns is how quickly they seem to pop up.Study Biology

You might check your garden in the evening and see nothing unusual, only to discover a bright red structure the next morning.

The explanation is that much of the fungus already exists in the soil or decaying organic matter. The visible mushroom is its fruiting body—the reproductive structure that emerges when conditions are suitable.

Stinkhorns often begin as small, egg-shaped structures near the ground. Under favorable conditions, the developing mushroom can expand rapidly, sometimes over the course of a day or two.

That's why a patch of mulch can suddenly look like the setting of a science-fiction movie!

Why Does the Red Stinkhorn Smell So Terrible?

Let's talk about the smell, because this is usually the detail that makes people stop in their tracks.

The odor of a mature stinkhorn is often compared to rotting meat, decaying animal matter, or manure. Some species produce a smell strong enough to notice before you even see the mushroom.

But the stink isn't a mistake.

It's part of the fungus's reproductive strategy.

The smell attracts flies and other insects

Many mushrooms release spores into the air. Stinkhorns use a different approach.

Their mature fruiting bodies produce a sticky, spore-containing material often called the gleba. This material can be olive-green, brown, or nearly black, depending on the species.Identify Plants

The unpleasant odor attracts flies and other insects that are drawn to decaying organic matter.

When the insects land on the sticky surface, spores can attach to their bodies. The insects then carry those spores to other locations, helping the fungus spread.

In other words, the smell that makes you want to back away is an effective invitation for the insects the fungus needs.

Nature has some wonderfully strange strategies, doesn't it?

The University of Florida IFAS Extension explains this insect-assisted spore dispersal process in its guide to stinkhorn mushrooms. Read the guide.

Does every red stinkhorn smell equally bad?

No. Odor intensity varies among species and with the mushroom's stage of development.

The smell is often strongest when the spore-bearing material is fresh and exposed. As the mushroom ages and dries out, the odor may diminish.

If the fungus has already begun to collapse, you might notice very little smell at all.

How to Recognize a Red Stinkhorn

<text color="secondary" size="sm">These are general clues, not a definitive identification guide.</text>

If you're trying to work out what has appeared in your garden, there are several features worth observing.

1. A bright red or orange color

Some stinkhorn species have vivid reddish-orange or coral-colored stalks. Others may be pale pink, white, yellowish, or orange.

Color can help narrow the possibilities, but it isn't enough to identify a mushroom by itself.

2. An unusual, upright shape

Many red stinkhorns grow vertically from the ground and have narrow, elongated bodies. Depending on the species, the top may be pointed, rounded, tapered, or covered with a slimy spore mass.

Some species have a relatively smooth stalk, while others appear pitted or spongy.Study Biology

3. A foul-smelling surface

A strong odor resembling decaying organic matter is a classic stinkhorn clue.

However, not every foul-smelling growth in a garden is necessarily a stinkhorn, so smell alone should not be treated as proof.

4. Growth in mulch or decaying wood

Stinkhorns commonly appear in wood-chip mulch, compost, leaf litter, and around decomposing plant material.

They may emerge after wet weather, when moisture supports rapid fungal growth.

5. A short-lived appearance

The visible mushroom may last only a short time. It can collapse, dry out, or disappear over the next several days.

The underlying fungal network may remain in the organic material, allowing another fruiting body to appear when conditions become favorable.

Important: If your fungus looks different from these descriptions, don't force the identification. Other fungi can have vivid colors and unusual shapes. A clear photograph of the entire structure, including its base and growing environment, can help a qualified mushroom identifier assess it more accurately.Source Farm Gear

Is the Red Stinkhorn Mushroom Dangerous?

This is probably the most important question for anyone who has found one in the backyard.

The answer depends on what you mean by dangerous.

Many commonly encountered stinkhorn species are not considered poisonous to people through ordinary contact, and they generally do not damage healthy garden plants. However, you should never assume that an unidentified wild mushroom is safe to eat.

The University of Florida's guide describes several stinkhorn species as non-toxic, but it also emphasizes the importance of accurate identification and does not recommend consuming them. Guidance can differ by species and location. Source: University of Florida IFAS Extension

Is it harmful to touch?

Simply being near a stinkhorn is not generally considered a danger.

Still, it's sensible to avoid handling unidentified fungi unnecessarily. If you do remove one, wear gloves, wash your hands afterward, and keep your hands away from your eyes and mouth.

Most importantly, don't let children or pets chew on or taste it.Identify Plants

Is it poisonous to dogs and cats?

The risk depends on the species and whether the animal eats it.

Some stinkhorns are considered non-toxic to humans, but that doesn't mean every mushroom is harmless to every animal. The Queensland Poisons Information Centre notes that stinkhorn fungi are generally not considered toxic as a group, while also describing anecdotal veterinary concerns involving some dogs. Source: Queensland Poisons Information Centre

If your pet has eaten an unidentified mushroom, contact a veterinarian promptly for advice. Don't wait for symptoms to appear.

What if a child eats one?

Take the situation seriously.

Remove any remaining mushroom pieces from the child's mouth, if you can do so safely, and contact your local poison information service or emergency medical service immediately. Save a sample or clear photographs if possible, but don't delay seeking advice while trying to identify it.

Wild mushrooms can be difficult to distinguish reliably, and some poisonous species cause symptoms only after a delay. Poison Control advises against eating wild mushrooms without expert identification. Source: Poison ControlStudy Biology

Are Red Stinkhorns Bad for Your Garden?

Here's some good news: in many cases, stinkhorns are simply part of a healthy decomposition process.

Fungi play an important role in breaking down dead plant material. As they decompose wood, leaves, and other organic matter, they help recycle nutrients within the environment.

Stinkhorns often grow in mulch because it provides a convenient food source.

They usually don't harm healthy plants

Unlike plant pathogens that infect living roots or leaves, stinkhorns generally use dead or decomposing organic matter as their food source.

Their presence in a mulched garden bed does not automatically mean your plants are sick or your soil is unhealthy.

In fact, the fungus may be helping break down organic material.

Why do they keep coming back?

Removing the visible mushroom doesn't necessarily remove the fungus growing beneath the surface.

The underground fungal network may remain in the mulch or decaying wood. If moisture and suitable food sources remain available, new fruiting bodies may emerge later.

That doesn't mean you're doing something wrong.Source Farm Gear

It simply means the fungus has found conditions it can use.

How to Get Rid of Red Stinkhorn Mushrooms

If the appearance or smell bothers you, you can remove the visible mushrooms. You don't necessarily need to eliminate every trace of fungus from your garden.

Step 1: Wear gloves

Put on gardening gloves before handling the fungus. Avoid touching your face, and wash your hands after finishing.Shop Lawn & Garden

Step 2: Remove the visible mushroom

Carefully lift or scoop out the fruiting body, including any visible egg-like structure near the base.

Place it in a bag or other container for disposal, following your local waste guidelines.

Avoid crushing or rubbing the spore-bearing surface unnecessarily.

Step 3: Dispose of it safely

Keep the removed mushroom away from children and pets. Don't put it somewhere animals might easily retrieve and eat it.

If you're unsure how your local waste service handles garden fungi, follow its guidance.

Step 4: Check the surrounding mulch

Look for very wet areas, piles of decaying leaves, buried wood, or other organic material where fungi may be growing.Identify Plants

You don't have to remove all your mulch. Organic mulch is beneficial to gardens, and stinkhorns are not usually a reason to abandon it.

If the area stays excessively wet, improving drainage or avoiding unnecessary watering may help reduce conditions that favor repeated fruiting.

Step 5: Give the area time

Stinkhorns are often short-lived. If you don't mind waiting, the visible structures may collapse and disappear on their own.

According to Iowa State University Extension, stinkhorns eventually wither away and can be raked or discarded if their appearance or odor is bothersome. Source: Iowa State University Extension

Should you use fungicide?

Usually, there is no need to reach for a chemical treatment just because a stinkhorn has appeared.

The fungus is often breaking down organic matter rather than attacking healthy plants, and removing the visible fruiting body may be enough to address the immediate problem.Study Biology

Avoid applying chemicals without a clear reason and appropriate local guidance.

Will Red Stinkhorns Come Back Every Year?

They might, but it's not guaranteed.

If the fungus remains established in the soil, mulch, or decaying wood, it may produce new mushrooms whenever conditions are favorable.

Moisture, temperature, available organic material, and the species involved all influence whether and when fruiting occurs.

You might see several mushrooms after a rainy spell, then none for months. You might also find that the fungus gradually becomes less noticeable as the available material decomposes.

There isn't a universal schedule for stinkhorn growth.

If you want to reduce repeat appearances, focus on managing excessively wet areas and removing decaying material that you don't want in the landscape. Even then, complete prevention may not be possible.Order Plant Seeds

Red Stinkhorn vs. Other Strange Backyard Growths

Not every unusual orange, red, or smelly growth is a stinkhorn.

A few distinctions can help you decide whether you need a closer identification.

Backyard discovery What it may look like What to know

Red stinkhorn Upright red-orange stalk or horn, sometimes with dark slime Often grows in mulch or decaying organic matter and may smell foul

Slime mold Yellow, orange, pink, or cream-colored mass spread across mulch Often looks like foam or a soft, irregular patch rather than an upright mushroom

Other mushrooms Caps, clusters, cups, or irregular fruiting bodies in various colors Some may resemble stinkhorns, so color alone is not enough for identification

Decaying plant material Discolored, softened, or rotting organic matter May smell unpleasant without being a mushroom

University of Massachusetts Amherst Extension explains that wood-chip mulch and compost can support several different fungi and fungus-like organisms, many of which are natural parts of the decomposition process. Source: UMass Amherst ExtensionIdentify Plants

If you cannot confidently identify what you've found, take a photograph and consult a local university extension service, mycological society, or other qualified specialist.

Frequently Asked Questions

Why did a red mushroom suddenly grow in my mulch?

The fungus may already have been present in the decomposing organic material. When conditions become favorable, the visible fruiting body can develop very quickly, sometimes within a day or two.

Does the smell mean the mushroom is poisonous?

No. A foul smell is a characteristic of many stinkhorns and helps attract insects that spread their spores. However, smell cannot establish whether an unidentified mushroom is safe or poisonous.

Will stinkhorns kill my flowers or vegetables?

Stinkhorns generally feed on dead and decaying organic material rather than healthy plants. Their presence alone does not mean your flowers or vegetables are in danger.Study Biology

Can I leave the mushroom alone?

In many cases, yes. If you're confident that it's a stinkhorn and there are no children or pets likely to eat it, you can allow it to break down naturally. If you're uncertain about its identity, keep people and animals away until you can obtain advice.

Should I remove the mulch where it grows?

Not necessarily. Mulch provides important benefits, including moisture retention and weed suppression. Removing an entire garden bed's mulch just because a stinkhorn appears is usually unnecessary.

Does removing one mushroom get rid of the fungus?

Not always. The visible mushroom is only the reproductive structure. The fungus may remain within the organic material and produce more fruiting bodies later.

Can I compost a stinkhorn?

Because identification and composting practices vary, follow local gardening or waste-management guidance. If the fungus is unidentified and children or pets could access the compost, keep it contained and out of reach.Shop Lawn & Garden

Can I eat a red stinkhorn?

Don't eat a wild mushroom based on a photograph, color, smell, or general description. Some stinkhorn species are reported as edible, but look-alikes and identification mistakes can be dangerous. Only consider consuming a wild mushroom after its identity and edibility have been reliably confirmed by a qualified expert.

The Bottom Line: That Strange Red Growth May Be More Natural Than You Think

Finding a bright red-orange, foul-smelling fungus in your backyard can certainly be startling.

One minute, your garden looks ordinary. The next, something that resembles a tiny alien has appeared in the mulch!

But if the growth is a stinkhorn, there's usually a simple explanation. It's a fungus using decaying organic material to grow and reproduce, with its unpleasant odor helping attract insects that carry its spores elsewhere.

In many gardens, stinkhorns aren't a threat to healthy plants and don't require aggressive treatment. You can remove the visible mushroom if its smell or appearance bothers you, or allow it to disappear naturally.Order Plant Seeds

Just remember that identifying a mushroom correctly matters. Not every strange growth is a stinkhorn, and an unidentified wild mushroom should never be eaten.

So the next time you spot something red, strange, and smelly in the garden, take a closer look from a safe distance. Nature is full of fascinating surprises—even the ones that don't smell particularly lovely!

Have You Found a Red Stinkhorn in Your Backyard?

I'd love to hear about your garden discoveries!

Have you spotted one of these unusual fungi in your mulch, compost, or flower beds? Did it appear after a rainy day, and did the smell surprise you?

Share your experience in the comments. If you have a photograph, it may also help others compare what they've found—but remember that a photo-based guess isn't a substitute for reliable identification.

And if you enjoy discovering the surprising things that grow around our homes, share this article with a fellow gardener who might be wondering what on earth has appeared in their backyard.Get Recycling Bins