Question
I just re-potted a tropical plant and noticed there is a white fuzzy mold on the surface of the soil.  It was not there prior to re-potting. I used regular potting soil, bone meal mixed in, and gave a light dose of Miracle Gro fertilizer in the 'transplant' strength.   

What caused the mold, and how do I get rid of it?  Will it harm the plant?  

I look forward to your response.

Answer
Hi Luisa,

For mold to form, there must be spores present in the soil. No doubt, the soil you used when you repotted contained the invisible spores. When the spores are exposed to moisture, then they start growing as mold.

The mold will not harm your plant. I suggest that you scrape off the mold and the loose surrounding soil and discard it. If you keep doing this and allow the soil to dry out more, then you may be able to get rid of the mold permanently. Applying a fungicide as a soil drench is another option. A third option is to remove and discard all of the soil you used and replace it with a sterilized, soilless potting mix.

Please let me know if any of this is unclear or if you have any additional questions.

Regards,
Will Creed, Interior Landscaper
Horticultural Help, NYC

You can E-mail me directly at: [email protected]

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