White stuff in soil
This appears to be a fungus growing on the top of the soil. We sometimes see this when the soil is damp all of the time and shaded. It should not hurt the plants and as it decays does release some nutrients and adds organic mater.
Fungal growth may be lessened by watering the plants less often so the soil on top dries out some between waterings. (Use a little more water at a time and water less often.) It may also help if you can remove a few of the lower leaves without hurting the appearance of the plant, This allows a little more light in which will help control the fungus and also more air circulation which helps lessen the moist conditions that the fungus likes.
Thank you very much for letting me know