For plant enthusiasts, indoor vegetation is a must for any home environment and aesthetic. Like kids, these green beings all have specific likes and dislikes and require assistance to live healthy lives. Plus, they provide a long list of benefits that can improve our happiness and wellness. What’s not to love? There is something that can negate all of the assets these green beings bring, though. Mold in houseplants can turn our leafy friends into a home health hazard.
That’s not to say they should be kicked out of our indoor spaces, though! Houseplants not only add pops of color to our indoor aesthetics but also help reduce noise and moderate indoor temperatures by providing shade. Some studies have shown that they can directly improve our wellness by reducing stress, boosting productivity, and improving our sense of well-being. ¹’²’³
However, to reap all the benefits, it’s essential to ensure that these living organisms aren’t bogged down with indoor contaminants like mold. Unfortunately, houseplants can offer a perfect habitat for this fungus among us, which is why this situation is such a common occurrence. Considering that the average American spends an average of 90% of their time indoors, plant owners must take the necessary precautions to ensure these little green beings aren’t battling mold for prime real estate and turning our homes into toxic warzones. ⁴
Here’s how to prevent mold on houseplants and what to do if it happens to your leafy friend, because no one wants to hang out with mold—especially our plants.
But First, Mold
Having a solid understanding of mold not only helps keep your plants safe, but it’s also a crucial aspect of home health. With how little it’s talked about in mainstream media and pop culture, misinformation is abundant. And that’s on top of the general lack of awareness of why indoor mold growth is a problem, how to prevent it, and what to do if it pops up in the home.
The more indoor contamination we can prevent, the healthier these spaces will be and the more they’ll support our ongoing wellness.
Mold Fast Facts
Mold is a type of fungus with over 100,000 species identified so far. An important thing to note is that the term "mold" actually refers to two things: a living organism and a non-living particle. The living organism is a growing colony that reproduces by creating and releasing microscopic particles called spores into the surrounding environment.⁵’⁶ Spores are the non-living portion of the mold.
Like seeds, these tiny spores will remain non-living particles until they land on a surface with the components needed for growth. Thanks to their hardy nature, most species of mold spores only require two main elements to begin growing. ⁷
These two puzzle pieces are:
If these are present for 24–48 hours, that mold spore will turn into a colony and begin the reproductive cycle all over again.
Why Mold on Houseplants Occurs
In short, houseplants are essentially moldy dream homes.
The organic material in the potting soil offers up an edible buffet for a lucky mold spore. Dead debris, such as leaves, creates another layer of options. The plant itself can provide sustenance for growth. And finally, organic particles floating around in that indoor air, such as skin cells, can also supply mold with life-giving energy.
As for moisture, plants need water to grow just as much as mold does. This can create the perfect opportunity for a spore to slide in and start growing right alongside the plant or directly on it. Before you know it, you’ll be growing a mold colony and your favorite species of vegetation.
The problem is that indoor mold growth does not provide the same health benefits as plants. Instead, mold on houseplants can turn your home into a health hazard.
Mold on Houseplants is a Wellness No-No
As mentioned above, when mold grows, it releases microscopic particles into the surrounding environment. When threatened, some mold species produce microscopic toxins known as mycotoxins, which add to the particle party in the indoor space.⁸ As the plant and mold colony are essentially fighting for nutrients, it’s a pretty safe bet that if the species can create these tiny toxins, it will.
Interestingly, while mycotoxins are regulated in our food products, they are not regulated in our homes.⁹
Their ability to impact our bodies largely rests on the size of the particles in question. Measured in a unit called a micron, these particles are invisible to the naked eye, meaning that they can just be hanging out in your home and you’d never know. The EPA classifies these types of particles as particulate matter and breaks them down into two categories. ¹⁰
These two categories are:
- PM10: particles that have a diameter of around 10 micrometers or less.
- PM2.5: fine particles that have a diameter of around 2.5 micrometers or less.
Because of their small size, they can be inhaled, ingested, and absorbed into the body and trigger negative health effects.¹¹ The longer an individual is in this toxic environment, the more these particles will enter their body.
A common misconception is that since mold is everywhere, it’s no problem when it’s in our homes. That’s not correct. We indeed encounter spores and mycotoxins throughout the day while walking into work or driving in the car—it’s impossible to avoid. When this happens, the body will tag them as foreign invaders and deploy the immune system to get rid of them. Mold on houseplants and inside our indoor environments does not create the same level of exposure.
Thanks to modern building practices pushing for net-zero energy efficiency, there’s minimal airflow between our indoor and outdoor environments. The result is that most of these particles will remain inside, creating poor indoor air quality and contaminated surfaces. This level of exposure is vastly different than just a few particles here and there throughout the day. The immune system will attempt to keep up, but battling an army of tiny particles can lead to it becoming overwhelmed and/or starting to malfunction.
This opens the door to chronic health issues.
What Are Common Symptoms of Mold Exposure?
The tricky aspect of indoor mold growth is that no two people react the same to exposure. While one person may experience a recurring headache and skin problem, another individual may develop over 30 symptoms and an autoimmune condition. Disorders such as Chronic Fatigue Syndrome, Aspergillosis, and Mast Cell Activation Syndrome can go hand in hand with chronic symptoms caused by toxic environments.
Much more research is needed to understand how this indoor contamination situation affects the body, but it’s a tough subject to nail down.¹²’¹³’¹⁴’¹⁵’¹⁶ Factors such as genetics, species of mold, length of exposure, presence of mycotoxins, presence of bacteria, and immune system status all play a role. For example, those with compromised or developing immune systems are more likely to develop symptoms faster and to a greater extent.
That being said, some common symptoms are seen in individuals suffering from exposure.
- Headaches and/or migraines
- Hormonal imbalances
- Hair loss
- Allergy/cold symptoms
- Brain fog
- Chronic fatigue
- Anxiety and/or depression
- Digestive issues
Again, though, every situation and reaction is unique. Some may not experience a reaction at all, but that doesn’t mean that all of the particles aren’t resulting in higher toxicity levels in the body.
The potential for adverse health effects is reason enough to add mold on houseplants to our wellness understanding and actively work to prevent this contamination in our homes.
How Do You Prevent Mold on Houseplants?
"Prevention is worth a pound of cure," especially when it comes to indoor mold growth. Several steps help prevent mold on houseplants and ensure your environment remains healthy. The key is to eliminate the components needed for growth and remove as many particles as possible that could opportunistically start to grow.
Steps to prevent mold on houseplants include:
- Use sterile soil: Start off on the right foot with your green friends by using sterile soil for seeds, changing the soil, or repotting brand-new plants. This will help ensure that mold isn’t present in the soil. Commercial potting soil is an option as it contains plenty of nutrients and is often sterilized by the manufacturer.
- Avoid overwatering the plant: Mold thrives in moist environments, so saturated plant soil is a no-no for home health. While all plants are different in terms of moisture needs, a good rule of thumb is to allow the top layer to dry completely before re-watering. You can use your finger to determine the soil's moisture level.
- Remove any extra elements: These can serve as an extra food source for a lucky spore and trap moisture. Getting rid of dead leaves, dust, or other organic debris can help keep your plant in tip-top shape.
- Invest in a dehumidifier: Where there are plants, there’s often a lot of humidity. Mold can grow in high humidity, so make sure to keep indoor levels between 35-50%.¹⁷ If this is a struggle, dehumidifiers can come to the rescue by removing excess moisture from the air.
- Consider using a fan: Creating air circulation can help dry out moisture faster. As mold can grow in 24–48 hours, this is key to preventing any contamination issues. Place a fan near the plant and keep it on a low level to help keep everything dry.
- Ensure proper drainage: Incorrect pot size or a lack of drainage holes can lead to water building up. Make sure that your pot is the correct size for your plant and that it has adequate drainage holes so that excess water can seep out.
- Provide light: Sunlight or artificial light will not only help your plant grow, but it will also help keep things dry and anti-mold.
- Consider using an anti-fungal: Adding things like cinnamon to the soil can help prevent mold as it’s a natural fungicide.
This isn’t an exhaustive list, but it’s a great foundation to help ensure mold on houseplants doesn’t happen to you.
How Do You Get Rid of Mold on Houseplants?
Mold is persistent. Even with all of the steps above, random events sometimes allow it to start growing.
First of all, it’s important to note that any and all mold growth should be treated the exact same way: quickly and correctly. You never know what the species could be or how someone could react, so it all needs to go.
If mold on houseplants happens to you, it’s important to take the right steps to resolve the situation so that contamination doesn’t continue to spread throughout the home.
Unfortunately, the absolute best way to deal with mold on houseplants is to get rid of the plant and start fresh. For hypersensitive individuals, this is especially important. Like plants, mold grows roots called hyphae that can reach deep into whatever surface it’s growing on. This can make getting rid of the issue extremely difficult.
To properly remediate mold, all of the contamination must go, including roots, dead mold, spores, mycotoxins, and bacteria. If roots are left behind, the mold can grow right back. High levels of those tiny particles present lead to continued exposure. Any remaining spores can result in the mold colony popping back up.
These factors are why remediating a plant is so difficult. The mold roots could have grown deep within the soil or on the plant itself. Not to mention, thanks to their tiny size, particles like mold spores and mycotoxins could have burrowed deep within the pot and be nearly impossible to remove.
Going For the Attempt
If, for whatever reason, you attempt to remove mold on houseplants, you need to go above and beyond to remove as much contamination as possible as well as the living colony (including those roots).
If you find mold on your plant, immediately put on protective gear and take it outside. Re-pot it using a brand new pot and sterile soil to eliminate as much contamination as possible. Also, shake out as much old soil as possible to remove any particles. Follow this up by using an anti-fungal and then keep a close eye on it. If the mold comes right back, it’s time to get a new plant.
When there is mold on the plant itself, take a microfiber cloth and start wiping off the mold. After each wipe, fold the cloth to a new side so you’re not spreading the contamination around. Continue with this for quite a few swipes to remove as much contamination as possible. Follow this up by using the repotting directions above.
Again, these aren’t ideal solutions as the chances of contamination remaining behind or the mold growing back is quite high.
How Do You Know If There’s Mold on Houseplants?
Determining if there’s a problem requires using the senses.
Grab a flashlight and look closely at any accessible area on the plant.
With so many species existing in the world, mold colonies can come in a variety of colors, shapes, and textures. Some of the most common colors include green, white, grey, blue, red, black, brown, or a combination of them. As for textures, they could be fuzzy, powdery, velvety, or slimy.
If any type of unidentifiable growth pops up, it's safe to assume there’s a mold problem that needs to be addressed.
Does it Smell?
Mold growth isn’t always visible. It could be in a hidden area like the soil, or the colony is too small to be visible to the naked eye yet. In this instance, look to your nose to help determine if there’s a problem.
Growing mold often creates an earthy, musty, damp smell due to the release of gases called microbial volatile organic compounds (MVOC).¹⁸ If this odor is coming from the plant, it points to a problem existing inside.
How Do You Feel?
Neither of those boxes is checked off, but do you still suspect a problem? First of all, always listen to your intuition! When it comes to indoor mold growth, instinct is a powerful tool to ensure we’re avoiding unhealthy exposures.
Our bodies are fantastic warning systems that will let us know when something is wrong, but we’ve got to listen to them when they sound off. If you start feeling unwell every time you’re around the plant, that can point to a moldy issue. Those invisible particles could be making their way inside of your body and wreaking havoc, causing your body to sound the alarm and push for you to get out of that toxic situation.
Safely Supporting Your Inner Plantohalic
All of this information isn’t to deter anyone from having plants. It’s to empower each and every one of us plant lovers to ensure our favorite green friends aren’t negatively impacting our health. Far too often, individuals struggle with chronic symptoms due to the indoor environments they spend time in, yet it’s rarely considered as a possible underlying cause.
Creating greater awareness and working to prevent mold in houseplants can help ensure our safe spaces promote our ongoing wellness. The last thing anyone wants is to walk over and see their poor plant covered in mold! Keeping this in your plant knowledge database can protect your indoor greenery and your body.
Health begins at home.™
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