White mold in plant soil: prevention and elimination

fungi in the substrate

fungus in the substrate

On many occasions we can see in the substrate of the plants how it looks like a whitish layer. This layer is made up of mold and it tends to appear more frequently when it comes to indoor plants that are arranged in pots. The substrate is usually a mixture purchased in stores and they are usually more prone to the appearance of these fungi. Although its appearance makes you doubt, do not panic. It does not always mean that it is something harmful to the plant. The appearance of white mold on plant soil it can colonize the entire substrate and be a danger or not.

Therefore, we are going to dedicate this article to tell you everything you need to know about white mold in plant soil and what it looks like.

Why does white mold grow in plant soil

white mold in plant soil how to remove

white mold in the soil of plants how to eliminate

The first thing to know is that you don’t always see a white layer of mold on the soil of the potted plants. It is very common that, especially when irrigated with tap water, a small amount of salt and lime builds up in the soil over time. This is because plants absorb nutrients and water from the soil, leaving behind these unwanted substances. At first it looks like white velvet, but as it builds up, it will eventually turn into a brittle coat. This layer is easy to remove by hand or by removing the first centimeter of the substrate, and then apply a little again.

On the other hand, if the white coating is wet, it is a white mold in the soil of the plants. It is also easy to identify by the way it spreads. You have to see if it quickly colonizes the entire substrate, even the plants. It is on these occasions when there is no longer any doubt that it is a fungus.

This situation is very common in mixtures of substrates and nutrients, because they create an environment that is also conducive to their development. When humidity and temperature conditions are high, this will occur in the soil and, together with the nutrients in the substrate, will promote mold growth.

In the case of saprophytes, they only feed on dead plant matter, so they do not pose any danger to plants or people. In any case, its abnormal accumulation will form a thick layer on the substrate, making it difficult for the plants to absorb water while retaining water. In these cases, it must also be removed.

How to remove white mold in plant soil

white mold on the ground

white mold on the ground

If you don’t know what type of mold is on the substrate, and these molds grow too large or produce an unpleasant odor, it is best to remove them just in case. Certain molds in the substrate can be harmful and attack our plants.

If the pot itself has mold, it should be cleaned thoroughly. Remove the root ball from the pot first, then carefully shake as much soil off the root as possible. If these are affected by mold, you can also trim them. After this, it is necessary to use a new substrate and a new container, or to sterilize the pot thoroughly.

If it is not so widespread in the pot, you can use an antifungal agent. Organic fungicides are always recommended more. For example, you can use milk dissolved in water and sprinkle it on the substrate. This way, you can spray the affected parts of the plant every day until the mold disappears.

It is also important to move the pot to a well-ventilated place and as dry as possible, and reduce watering of plants while still treating the fungus. If there is not enough water, it will be much easier to remove the mold.


mold contaminating the plant

mold contaminating the plant

In most cases it is better to prevent the appearance of fungus before trying to eliminate them. Preventing the growth of mold in the soil of plants is as simple as providing conditions that are not compatible with fungi: ventilation and low humidity. Obviously, it is not about stopping watering the plants, but waiting for the substrate to dry a bit before watering will help a lot. What’s more, It is important that if the plant is in a pot, it has drainage holes to avoid the accumulation of water.

As for aeration, it is enough to make sure that the plants are in a position where the air circulates naturally. However, some species are damaged by currents, so it is not recommended. In these cases, all you need to do is gently remove the top layer of the substrate, and we will not damage the roots. By stirring the substrate well, it will also naturally expel air, which will hinder the growth of fungi.

It is also important to provide the plants with the necessary fertilizer, neither excessive nor lack of fertilizer, and always remove the residues of fallen leaves and flowers from the soil or substrate. A good option is to use a tray to water under the plants instead of spraying water from above. This can only be left for a few minutes, and then withdrawn or put in an adequate amount of water each time to prevent puddles from forming at the roots. Puddling can lead to not only other fungi appeared, but also root rot.

Care errors

There are some mistakes in the care of our plants and none of us want to have them, let’s see what are the main aspects of fungi that can grow in the soil of plants:

  • Small ventilation environment: this is a typical situation in the coldest month of the year. Due to the low temperature, we tend to reduce the ventilation time at home.
  • Warm temperature: It is the decisive factor to avoid the growth of fungi in the vegetable soil.
  • High humidity: It is the main reason for the appearance of fungi in the vegetable soil.
  • Decomposing substances in the substrate: Although they can be beneficial for our plants in small amounts, if we add the above all the factors can eventually create a perfect breeding ground for fungi.

I hope that with this information you can learn more about white mold in plant soil and how to eliminate it.

White mold in plant soil: prevention and elimination

Leave a Reply

Scroll to top

Discover more from DIY Gardens

Subscribe now to keep reading and get access to the full archive.

Continue reading