I recently purchased a variegated pink lemon tree. This is my first citrus tree and I really know nothing about how to upkeep it. :( I have it in a container so that I can bring it in for the winter months. My problem is that several of the leaves are started to roll into a tight roll. When I open them up and look underneath, it is all black and moldy looking. Anyone know what this is and what I should do??? Thanks for any help!