Potting soil is moldy: causes and measures

Potting soil is moldy
You can do that!

© matuska / Shutterstock

If a white coating covers the potting soil, it could be mold. Not only is it unsightly to look at, it can also be dangerous! Here you can find out what you can do if your potting soil becomes moldy.

How do I know if there is mold on the potting soil?

  • If a white coating can be seen on the potting soil, the one soft, fluffy consistency has, it is about Mould. At first it occurs in small colonies, later it is visible over a large area, runs through the earth with its mycelium and can even develop fruiting bodies. In addition, mold is usually accompanied by a musty smell. If mold is visible on the potting soil, the plant must be repotted!
  • On the other hand is a white one crumbly, hard topping recognizable, it could also be Mineral deposits act. For example, lime-rich water can leave lime residue on the potting soil when it evaporates, or fertilizer can lead to deposits. In that case, the residue can simply be scraped off the surface with a spoon and new soil can be filled in. Tip: If you live in areas with lime-rich groundwater, you can use rainwater as irrigation water.

Potting soil is moldy: you can do that

Mold spores can lead to diseases and allergies, so you should repot the plant as soon as possible!

You need:

  • Hand shovel
  • Vinegar + warm water for cleaning
  • brush
  • Pottery shards and expanded clay (alternatively gravel) for drainage
  • High quality potting soil
  • sand

Note: It is best to repot the plant outdoors and thoroughly ventilate the room in which the plant was. Mold allergy sufferers and people with a weakened immune system should wear a face mask when repotting moldy soil!

That's how it's done:

  1. Use a hand shovel to remove the moldy potting soil.
  2. Lift the plant and its root ball out of the earth and remove the remains of the earth as possible.
  3. Rinse the roots of the plant with lukewarm water.
  4. Use a brush and warm vinegar rinse to clean the inside and outside of the pot to completely remove mold spores.
  5. In order to avoid waterlogging in the future, first place pottery shards and then a two to three finger thick layer of expanded clay over the drainage hole: This creates drainage.
  6. Put the plant in the flower pot and fill the pot with fresh soil mixed with some sand. The sand loosens the soil and allows excess water to drain off better. Caution: Do not press the earth's surface hard!

Why is mold on the potting soil dangerous?

Fungal spores permeate the air we breathe. The conditions for mold are given with organic material, moisture and warmth. As a result, it can quickly happen that mold spreads rapidly on heavily watered potting soil. This increases the concentration of mold spores in the room air, which can pose a health risk. Depending on the type of mold, Allergies triggered, irritations caused or even infections caused – especially People with weakened immune defenses or respiratory diseases must be careful here! The mold can also be dangerous for the young plants: with intensive competition for nutrients, the plant could perish.

How can you prevent mold on the potting soil?

  • Use clay pots:Due to the porous properties of the material, moisture can escape better and waterlogging can be avoided.
  • Always use for repotting high quality soil: In addition to wood fibers, it also contains pieces of bark, which ensure that the earth remains loose. Cheap potting soil, on the other hand, contains a high proportion of black peat and compost, which tends to contribute to the compaction of the potting soil and thus lead to mold.
  • If stored poorly, the potting soil can already mold in the packaging: For example, if condensation forms and the bag is in a warm environment. To prevent this, the potting soil should be stored in a dark, cool place and protected from moisture.
  • Loose soil prevents mold: Regularly walk through the soil with a fork or something similar to loosen it up.
  • Sprinkle something in addition Sand on earth, this dries out the surface faster.
  • Only water your plant when it is necessary! Many plants are actually watered too often and too heavily. The result: waterlogging and ultimately mold! It is better to pour a little less water on the plants and only when the surface of the earth is already dry. Tip: In the autumn and winter months, many plants require even less water than usual!
  • Repot your houseplants regularly.
  • Put your plants in one brighter place, it dries out the earth better.
  • Ventilate your rooms regularly.

Looking for more tips and tricks about plants? Here you will find useful information about planting herbs, filling the loft bed and creating compost.

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