Preventing Mold In The Soil Of A Houseplant


By: Heather Rhoades

Mold allergies are a common affliction that affects many people. Unfortunately, there is not much that can be done to treat mold allergies beyond the age-old advice of simply avoiding sources of mold. If a mold allergy sufferer keeps houseplants, it is important for them to keep the soil of their houseplants free from mold.

Controlling Mold in Houseplants

Mold in the soil of houseplants is common, but mold control on indoor plants can be done if you follow a few simple steps:

  • Start with sterile soil – When you bring a new plant into your home, repot it using sterile soil. Your plant may have come home from the store with mold in the soil. Gently remove all the soil from the plants root ball and repot in new, sterile soil. Most of the time, the potting soil you buy at the store has been sterilized already, but you can sterilize your soil in your oven if you want to be doubly sure.
  • Water only when dry – Houseplant mold normally happens when a plant is kept continually moist. This condition happens when you either over water or water on a schedule instead of by touch. Always check that the top of the soil is dry before you water your plants.
  • Add more light – More light is an excellent way to do mold control on indoor plants. Make sure your houseplant gets plenty of sunlight and that the sunlight falls on the soil.
  • Add a fan – Mold in the soil will stop happening if you make sure that there is good air circulation around the plant. A simple oscillating fan set on low will help with this.
  • Keep your houseplant neat – Dead leaves and other dead organic material add to the problem of houseplant mold. Trim dead leaves and stems regularly.

With just a little bit of extra effort, you can keep houseplant mold to a minimum. Mold control on indoor plants will let you enjoy your houseplant without having to suffer for it.

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How to Treat and Prevent Moldy Soil

Seeing mold in your potting soil is disappointing, alarming, and frustrating. Even when you think you’re doing everything right, this white fuzzy growth can make any growing experience feel like a failure.

Before you dump your plant and soil in the trash, however, there’s hope!

In this blog, we’ve explained some of the best ways to address and kill any mold growing in your pots. We’ll help you understand why it molded in the first place and what you can do to prevent it from coming back.


How to Get Rid of Mold in Plant Soil

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The mold that is visible in your soil is likely a saprophyte -- a harmless mold -- and soil rich in organic matter often contains it, though it is usually not seen. While the mold may not harm your plants, it indicates that the environment around your plants is most likely susceptible to disease, such as root rot. Remove the mold to improve the aesthetic quality of the soil, and make some cultural changes to improve the growing conditions for your plants.

Scrape off surface mold and discard it. Use a spoon or knife for a houseplant. Outdoors, use a trowel or shovel to carefully scrape the mold off.

Till the soil in large areas with a tiller, spade or garden fork. If the mold is growing near plants, carefully use a small, hand-held garden fork that you have more control over so you do not harm the roots. For potted plants, repotting may be necessary, using fresh, high-quality potting soil. Turning the soil aerates it and relieves compaction, which may cause drainage problems.

Allow the soil to dry out between waterings. For plants that require moist soil to thrive, wait until the surface is dry, then water. For plants that can tolerate some dry soil, wait until the soil dries out 2 or 3 inches deep before watering. When you do water, water deeply so you do not need to water as often. In the garden, apply 1 inch of water. For potted plants, water until the water drips out the drainage holes.

Keep the area on top of the soil clean and free of debris. Rotting leaves and plant parts may be a haven for fungal growth. Trim nearby shrubs and trees to increase sunlight exposure, which will help keep the soil from staying too wet.


Why is there Mold on the Soil of My Plant?

The white fluffy stuff on the plant soil is most likely a harmless saprophytic fungus. Too much water, poor soil drainage, contaminated potting soil, and a lack of sunlight can all cause fungal problems (mold) on the plant soil. The “perfect” environment for white mold on house plants to grow is dampness and low light.

The mold fungus is made up of tiny microscopic spores, and they start to grow and flourish in certain circumstances. Depending on the cause of potting soil contamination, the mold can vary in color.

Here are some types of fungi that can affect your houseplants.

White fungus on soil

The Royal Horticultural Society says that white thread-like growths on dirt are saprophytic fungi. This white fungal growth—also called mycelium—is harmless, even if there’s lots of it. (1)

Yellow fungal mold

Yellow mold growth on plant soil is also a type of harmless saprophytic fungi. You can get rid of it by scraping it off or repotting the plant in sterile potting soil.

Gray mold on houseplant soil

Some types of gray mold can be a kind of fungus called Botrytis. This fuzzy growth is usually found near the soil surface or growing in dense foliage. Gray mold can harm the plant if left untreated.

Sooty mold

Patches of black or dark green soot-like substances could be a sign of scale. These tiny insects can suck the life out of your plant as they feed on the plant’s sap. The sooty mold isn’t harmful to the plant, but you need to get rid of scale insects quickly.

Powdery mildew

Houseplant fungal problems can look like a dusting of flour called powdery mildew. If this fungus problem gets too large, it can affect the plant’s photosynthesis and stunt its growth.


Don't wait till it is too late, AdvantaClean can help, request a service appointment today!

Decrease your exposure to mold by cleaning mold from the leaves of your houseplants. Mold found on living plants can easily be wiped away. Warning: never do this with a dry paper towel, or you'll wind up spreading the mold spores in the air.

Replace the paper towels when you're cleaning to prevent the accumulation of dust & mold from spreading. Make sure you're cleaning in a well-ventilated area, and use a spray bottle to make the cleaning overall easier.

Removing mold from the soil itself will take a bit more effort. You need to scoop the top layer of soil that's infested with mold using a spoon or a spade to strip that layer and place it into a plastic bag for easy disposal.

Replace the stripped top layer of soil with new potting soil - but only after you've removed all traces of visible mold. If the infestation is too far gone, you'll need to replace more than just the top layer to prevent further exposure to mold.

Add a natural, organic anti-fungal substance to your soil to keep any mold spores from growing. Cinnamon is a great option, and will deter the growth of mold and is harmless to the plant itself.

To prevent mold from growing back, place a thin layer of gravel on the bottom of your potting mix, allowing for a much more effective method of draining.

Keep your houseplants in a well-ventilated area. Mold thrives in areas with poor ventilation, so make sure you open a window, use a dehumidifier, or run proper ventilation fans.

HOUSEPLANTS, PREVENTING EXPOSURE TO MOLD:

Start with sterile soil. When bringing a new plant into your home, re-pot it using sterile soil because your plant may originally have come home from the store with mold in its soil. Do this by gently removing all the soil from the plant's root ball and re-potting it.

Water your houseplants only when they're dry. Exposure to mold usually happens when a plant is kept continually moist. This happens when you either over-water your houseplants or water on a schedule instead of by touch. Always check that the top of your houseplant's soil is dry before you water it.

Add more light. Mold loves the dark, so a great way to control moisture on indoor plants is to make sure they get plenty of sunlight, and more importantly that the sunlight falls on the soil.

Add a fan. As discussed above, adding a fan will reduce your exposure to mold because mod in the soil will stop happening if you make sure there is good air circulation around the plant. A simple oscillating fan set on low will help with this.

Keep your houseplants neat. Dead leaves and other dead organic material add to the problem of exposure to mold. Be sure to trim dead leaves and stems regularly.

WHERE ELSE CAN YOU FIND MOLD IN YOUR HOME?

Exposure to mold isn't limited to houseplants. Worst of all, mold is sneaky. To find it, check in these unusual places that provide mold with the food and water it needs to grow:

Also you can't forget about the guts of your home including:

Drywall, Subflooring, Heating and air conditioning filters, and the HVAC ductwork

WHY SHOULD YOU CARE ABOUT EXPOSURE TO MOLD?

According to the Centers for Disease Control and Prevention (CDC), mold exposure can cause symptoms such as nasal stuffiness, eye irritation, wheezing, and skin irritation. People with serious allergies to molds may have more severe reactions including fever and shortness of breath and those with chronic lung illnesses, like obstructive lung disease, may even develop mold infections in their lungs.

Exposure to Mold is Worse for Infants

Because of their not-yet-developed immune systems, infants and young children are of special concern when it comes to mold spore inhalation. Infants are more vulnerable to toxic exposures and ingest more dust than adults since they (and their toys) spend a lot of time on or near the floor. (Scientists once thought children were getting lead poisoning by chewing on windowsills but we've since learned that it's actually caused by lead is a component of toxic dust and mold.) Environmental Working Group found that ingestion of these spores can cause deficits in learning as well as motor skill and memory development

Call 877-957-5670 to schedule an appointment with an AdvantaClean Mold Specialist today!


How to Prevent Mold in Your Greenhouse

To prevent mold in your greenhouse, it all comes down to water, air, and cleaning. If you get these three basics right, then your greenhouse has a much better chance to stay mold-free.

To prevent mold in your greenhouse, control moisture and air circulation, and clean thoroughly.

Mold is a fungus that grows best in warm temperatures. Mold also requires high humidity (above 85%) in order to thrive. Standing water is another factor that can help mold to grow.

If we can control the water and air circulation, then we can prevent mold in most cases.

Carefully Control Water and Air Circulation in Your Greenhouse

The leaves of your plants are one potential breeding ground for mold, so it is important to water them properly and keep the foliage dry, if possible.

Keep Your Plant Leaves Dry

Wet plant leaves give mold the perfect place to grow. After mold is established on a plant, it can easily spread to nearby plants, causing an all-out mold infestation.

One of the most important steps in preventing mold growth in your greenhouse is to keep plant leaves dry. This sounds easy, but there are a few things to keep in mind.

Keep your plant’s leaves dry – wet leaves invite mold growth.

First, avoid misting your plants with a hose attachment, watering from overhead, or using foliar sprays. All of these will wet the foliage and invite the growth of mold.

Instead, water your plants close to the soil, to avoid getting the leaves wet. Consider side-dressing the plants with any nutrients they may need by working it into nearby soil and watering it in.

Also, be careful of where you put your plants. Avoid putting them underneath places where condensation drips down from the plastic or glass ceiling of the greenhouse. Otherwise, the leaves will get wet, which will lead to mold growth as described above.

Finally, water your plants in the early morning, not at night. Watering in the morning, when the air is cooler, gives the water time to soak into the soil and get to the roots of plants.

If you water later in the day, the heat and sun will cause more of the water to evaporate. This leads to high humidity levels in the greenhouse, which invites mold growth.

Avoid Over Watering Your Plants

Over watering your plants is another mistake that will cause mold growth in a greenhouse. When plants are over watered, the soil contains more moisture than the plants can use.

Do not over water your plants, or the soil will stay too wet and become a place for mold to grow.

If the soil stays too wet for too long, mold can grow directly on the surface of the soil. It can then spread to plants or over the soil to colonize the entire greenhouse.

To avoid this problem, water your plants deeply, but less often. This will give the soil a chance to dry out between waterings, which will prevent mold growth.

Always check the soil moisture before watering – if it already feels moist, then there is no need to add more water. In fact, you can “kill your plants with kindness” by over watering.

Leave Enough Space between Plants

In addition to controlling moisture levels in your greenhouse, it is also important to allow for proper air flow. One way to do this is to leave enough space between plants.

First of all, this allows air to flow more freely between plants. This allows any water on the plants or in the soil to evaporate, instead of staying put and providing a place for mold to grow.

Also, leaving space between plants prevents mold from spreading quickly if you do have an outbreak in the greenhouse.

Allow Ventilation in Your Greenhouse

Leaving enough space between your plants is only half the battle. To allow fresh air to replace stale air in the greenhouse, you will need to open vents or doors on the greenhouse.

If your greenhouse has vents, open them up to let some air in.

You can also use fans to circulate air and dehumidifiers to dry out the air in your greenhouse. Also, remember to keep these machines clean to avoid blowing mold spores around.

Keep Your Greenhouse Clean

Maintaining proper moisture levels and air circulation in your greenhouse is important for preventing mold. Once you have done this, it is time to come up with a plan for keeping the greenhouse clean, including tools of the trade (pots and containers) and the structure itself (glass, plastic, wood, or metal surfaces).

Sterilize Pots, Containers, and Tools

To keep mold at bay, you should have a regular cleaning schedule for any tools you use in the greenhouse.

Even if you don’t see any mold growing, it is important to clean to get rid of any mold spores that are waiting for the right time to start a new colony. Start by sterilizing your pots and containers.

Sterilize your pots and containers to avoid spreading mold from one year to the next.

First, empty out the soil and plant matter from the pots. You can add the soil and plant matter to your compost pile and reuse it next year.

Next, rinse off the soil from the pots, and use a rag to wash them with soap and water. Rinse the soap off of the pots.

Then, soak the pots in a solution of water and vinegar (3 parts water, 1 part vinegar) to kill any mold.

Finally, rinse the pots off with clean water and let them dry. Store them in a clean, dry place for next year.

You may also want to sterilize your gardening tools, such as pruning shears, on a regular basis. To sterilize your tools, use a clean rag and some rubbing alcohol to wipe them down and kill any pathogens.

This will prevent the spread of diseases between plants, and a healthy plant is more likely to resist mold growth.

Clean Surfaces between Seasons

In addition to cleaning the tools and containers in your greenhouse, it is important to clean any surfaces that may harbor mold growth. This includes:

  • the top and all sides of metal containers
  • the top and all sides of wooden benches
  • plastic or glass panels used for the tops and sides of the greenhouse structure itself

To clean the surfaces in your greenhouse:

  • First, remove any debris from the surface, including dirt or dead plant matter.
  • Next, wipe away any remaining dirt or dust with a wet rag.
  • Then, use a vinegar solution (1 part vinegar to 3 parts water) to wipe down the surfaces. You may want to wear gloves for this step, since vinegar can be nasty on your hands if they are exposed for too long.
  • Finally, wipe the surfaces with a dry rag to get rid of any excess water and vinegar.

Just like you schedule a time to start seeds and transplant seedlings, you should schedule a time to clean your greenhouse and keep it mold-free.


How do I prevent moldy soil?

When you’ve killed the fungus, or if you simply want to prevent it from growing in the first place, there are several steps you should take.

Don’t overwater

The easiest way to prevent mold is to only add water when it’s needed. Carefully check the moisture level of your soil before adding more water. If you don’t have a moisture meter, you can use your finger to see if the top 2” of your soil is dry. Only water your plants if this is the case.

Give plants plenty of sun

Sunlight will help manage soil moisture levels and kill mold. Make sure to keep your plants in an area that gets the right amount of sunlight.

Remove dead leaves

If any leaves or plants die and fall onto the soil, remove them as soon as you notice them. Rotting vegetation creates a great environment for mold, so this will lower your chances of a fungus invasion.


Watch the video: How to Remove and Prevent WHITE MOLD ON SEEDLINGS!


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