Hi,
I bought what I think is a juniper bonsai tree from a craft show a couple months ago and the seller told me to keep it in the pot in the plastic tray and then keep the water filled to the brim of the tray, but to never water the soil directly. I've done that and kept it near a sunny window for the entire time but today I noticed that there is white mold growing all around the soil and there is a white spot (not mold) on one of the branches. I guess I've overwatered it? But I don't know...I'm completely new to bonsai trees (and basically caring for any plants in general) so please, PLEASE help!