When White Mold Grows on Potting Soil

white fungus grows in pot soil

When you garden for a long time indoors, you will eventually get caught up in this situation. White mold appears on the soil surface of a houseplant or some seedlings. what is that? And is it harmful? And how to get rid of it?

what is that

Mold is a type of fiber fungus. (I can not say more precisely than that, because there are hundreds of species and dozens of species that all look the same.) Such fungi are always present in our environment: their spores float in the air both inside and outside. Germinate if they find a substrate that is suitable for them. Also, there may be spores in the potting soil you buy. Or the plant may have been in the purchased greenhouse. Or carried in a pot tool. Or your fingers ...

What can I say? Fungal spores are everywhere!

This type of fungus is saprophytic: it lives on decomposing particles of organic matter (wood, charcoal, leaf mold, etc.) found in the potting mix. It is not pathogenic or directly harmful to your plants… or harmful to people or pets. In fact, it really helps your plants because it contains minerals in the organic matter that are digested, which are released. So your plants can absorb them and use them for their growth.

In other words, white mold is part of the composting process, but composts in a pot rather than in a pot! Slow decomposition of potting soil by various soil organisms (very invisible to the naked eye) is part of the life cycle and usually goes unnoticed. The appearance of white mold in the workplace of Mother Nature is one of the rare examples.

How to get rid of white fungus

So, white mold in pot soil is normal and beneficial to a certain extent, but you still do not like it. First, for aesthetic reasons, perhaps. However, some varieties form a network of very dense mycelium, which impedes the circulation of air and water to the roots of the plant and you certainly do not like it. In any case, it is better to remove it.

Take a fork and wipe the top surface of the potting soil (it can be a compost pile or even go directly into the garden) to a depth of about 1 inch (2 cm), then place fresh soil. This is usually enough.

Occasionally if it comes back (which is very rare, but some species are more persistent than others), you will need to replant the plant, remove the old pot mixture and replant in new soil in a clean pot.

Prevention

Decomposition continues in all potting soils but is generally invisible. The presence of mold is usually associated with excessive humidity, poor drainage, or poor air circulation: things you can fix. The current renaissance in the market for pots without drainage holes is one reason why white mold is more common than in previous years.

Here are some suggestions on how to look or get an appointment for pottery:

1. Let the soil dry between irrigations

A bit for seedlings, cuttings, and most houseplants; Very deep for succulent and other arid climate plants.

2. Increase air circulation

You can turn on a fan in the living room, for example, or break a window.

3. Avoid dense, heavy soils

Soil from the garden, especially. Light, well-ventilated potting soil, widely available commercially, is the best choice.

4. Remove fallen leaves or other debris

They can be a source of fungus or help to grow fungi.

5. Replant plants growing in pots without drainage holes in the most suitable containers

6. Give more light to your plants

That way, they will use the water faster and the potting mixture that does not like mold will dry out faster.

7. Remove the mulch

Mulch is generally good for plants, but in conditions of poor air circulation, high humidity, or poor drainage, it can stimulate fungal growth. Or use chopped sphagnum moss as mulch: it has natural anti-fungal properties.

8. Use fungicide

I mention this as a last resort because I feel there is no need to “pull out the big guns” for a small problem like this. However, yes, commercial fungicides can help prevent the fungus or slow its growth, as well as homemade products such as cinnamon powder sprayed on the soil or chamomile tea.