Yellowish Crust (Peat Mold)

Yellowish Crust (Peat Mold)

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Yellowish-brown powdery crust on your plant's soil surface can develop as a result of peat mold. Fungicides typically aren't very effective against this type of mold, however, it's not harmful to your plant just more of an eyesore.

Peat mold (and mold in general) develops in moist, humid conditions such as a well-watered house plant soil, particularly if the airflow around that plant is poor. If you see this mold, it may be an indication that the soil is staying too moist for long periods of time. This is another reason why it's important not to overwater your plants. As much as the mold itself isn't usually harmful, overwatering can cause a lot of damage.

This type of mold only develops in decaying organic material, like peat, which is where it gets its name. You don't need to worry about it spreading onto your living plants.

Peat mold


  • A crust on top of the soil, ranging in color from yellowy-orange to brownish, and often powdery in consistency

  • There may also be white mold on the soil surface too

  • Sometimes there may be a 'damp' odor surrounding the affected plant