White Fungus Balls in Soil: What To Do Next

Eeeek! White fungus balls have appeared in your plant’s soil and are starting to cause panic!

What does it mean? Will they harm your plants? Are the white fungus balls toxic for humans and pets? Are they insect eggs? Well, stick around because we are about to find out about the good, the bad, and the ugly!

The white balls you discovered in the soil are most likely mushrooms. When conditions are right, mushrooms will seemingly appear out of nowhere, popping their little heads out of the soil. Unbeknownst to you, they were hiding in your soil the entire time and lying in wait until they had enough food and energy to grow. It is a good sign if the white balls turn out to be a variety of fungi because it indicates that your soil is healthy. However, your white balls may be eggs, so further investigation is required. We’ll tell you how to tell the difference in the next section.

White Fungus Balls in Soil – What Are They?

Before we get into what to do about your white fungus balls, let’s first confirm that they are, in fact, fungus and not anything else sinister, like pest eggs.

Are the White Balls A Type of Mushroom?

When you think of a mushroom, you generally picture that quintessential broad mushroom cap and stem structure. However, when mushrooms are still immature and begin to push out of the soil, they can appear like little white fungus balls. Here is a picture of a mushroom poking out of the soil.

An excellent way to be confident that your white fungus balls are mushrooms is to observe them over a few days. Mushrooms proliferate and will develop into the cap and stem mushrooms we know within 24-48 hours.

Identifying the type of mushroom growing in your soil can be difficult. According to Wikipedia, approximately 14,000 different species of mushrooms have been identified. So how do we know which one you have?

Generally, two types of mushrooms produce white fungus balls AND commonly pop up in houseplant and garden soil. These are:

Stinkhorn Fungus Mushrooms is an interesting variety of fungi belonging to the Phallaceae family. As their name suggests, this variety of mushrooms emits a foul smell with sticky spores. When they first appear in the soil, they appear as fuzzy white balls but quickly develop into short tubby stems with a small mushroom cap. The mushroom attracts animals with a foul smell and spreads its spores by sticking to the animals’ coats.
Puffball Fungus Mushrooms – unlike the stinkhorn variety, puffball mushrooms consist of 20 different types of mushrooms. They are grouped under the one catchall term because they share similar characteristics. They all appear as white balls in the soil, with no visible stem like other mushrooms. When they first appear, they will be small white fungus balls. However, as they mature, the white balls will grow roughly the size of a golf ball (or more prominent if the environment allows). They can sometimes grow under the soil’s surface or only be partially visible.

Are the White Balls Eggs?

If, after a few days, your white balls remain the same size, then it is likely they are not a type of fungi.

The white balls may actually be eggs laid by a garden pest.

The most likely culprit for the white eggs are:

Fungus gnats – adult fungus gnats seek out moist soil to lay eggs. They are commonly found in houseplant soil because indoor plant owners often overwater their plants, resulting in damp soil. Fungus gnat eggs look like small round balls clumped together on the soil’s surface (or near the surface). Their color can range from a dirty yellow to off-white. Gnat eggs have a short gestation period, only lasting 5-7 days before the larvae hatch. So, if you suspect you have gnat eggs, get rid of them quickly.
Slugs – will lay eggs around your plants’ soil in small clusters or clumps approximately one inch in diameter. The eggs can vary from white to cream-colored balls and usually contain around 30 eggs per cluster. Slug eggs take about one month to develop and hatch, giving you plenty of time to observe and investigate the mystery white balls in your soil.

What To Do About White Fungus Balls in Soil

So now that you can identify your white mushroom balls – what do you do?

In this section, we’ll discuss the next steps you can consider depending on your identification of the white fungus balls.

Mushrooms

In truth, you don’t need to do anything if you have mushrooms growing in your soil. As we mentioned earlier, their presence indicates that your soil has plenty of organic matter and is thriving.

That said, we can understand that white balls in your soil may not be the look you had in mind when you started your indoor or outdoor garden. If the aesthetics of the white balls disrupt your overall look, the obvious next step would be to remove them.

Plus, stinkhorn mushrooms do emit a foul smell. If they are growing in your houseplant soil, your house may be subject to some very smelly odors.

How to Remove Mushrooms from Your Soil:

Manual removal – with rubber or gardening gloves, carefully pick the white fungus balls from the soil. Carefully displace the top soil to see if other mushroom buds are growing. Remove these too.
Replace with fresh soil – mushrooms grow from the white, threadlike roots called mycelium. The mycelium spreads throughout the soil, waiting to spawn more mushrooms. Therefore, you must replace the soil clumped with mycelium and other fungal spores to prevent more mushrooms from growing.
Organic removal – one of our favorite ways to tackle mushrooms in potted plants is to use natural organic fungicides. We usually sprinkle some fresh cinnamon powder or a diluted form of white vinegar onto the soil of our plants. Both substances are natural fungicides and can even benefit some particular plants with healthier growth. Plus, you can easily find them in your kitchen pantry!
Dry them out – mushrooms require moisture to thrive. They will soon dehydrate and die off by depriving them of any water content in the soil. Of course, this should only be done, providing your plant can handle the dry periods.
Bottom watering houseplants – as we said before, mushrooms require moisture to grow. By bottom watering your houseplants, you can keep your topsoil dry yet still, providing enough water for your houseplants. You can read our guide HERE if you haven’t bottom watered your plants before.
Use fungicide – although this is usually our last option, if you want quick definite results, using a plant-safe fungicide will get you to the end goal. You should be able to source them from your local nursery or online in marketplaces like Amazon.

Garden Pest Eggs

The solution is simple if you suspect the white balls in the soil are garden pest eggs. Get rid of it quickly!

The process should be as easy as scooping them out with a trowel or small spoon and disposing of them.

Make sure to inspect the loose soil where you found the eggs thoroughly. There are likely more eggs hiding. Loosen the top inch of soil to ensure you don’t miss any hidden beneath the soil surface.

White Fungus Balls in Soil – Common Questions

Are white fungus balls harmful to plants?

ANSWER: No, white fungus balls will not harm your plants. The presence of fungi in your soil is a positive sign that you have healthy, thriving soil rich in organic materials.

Are white fungus balls harmful to humans and pets?

If the white fungus balls are left alone, they are harmless and will not impact your children or pets (except for possibly some foul smells from stinkhorn ball mushrooms).

However, some mushroom varieties are known to be toxic if consumed. Therefore, if you want to eliminate the possibility of any accidental poisonings from occurring, we recommend removing them from curious little hands and paws.

Do white fungus balls smell?

It is worth noting that not all varieties will smell. Yes, some white fungus balls may emit a smelly odor. For example, stinkhorn fungus are known for their foul smells (hence the name).

How do you prevent fungal balls from growing?

You can sterilize the soil with heat if you are adamant about preventing fungi from growing in your potting soil. The heat will kill fungi spores, leaving you with clean spore-free soil. That said, you will also kill other beneficial fauna in the potting soil. So there are both positives and negatives to the process.

You can also try bottom watering your houseplants to maintain a dry environment around the topsoil.

How long do white fungus balls live?

Mushrooms generally have a short lifespan, lasting between 2-4 weeks. However, if conditions are optimal, it may seem like they stay longer because new mushrooms often shoot up to replace the older mushrooms.