I got my snowball bush a couple years ago as a little twig. At first it turned green and even had a few blooms that year. Then last year I saw black spots on the leaves and it looked like it was dying. We were told it might be drowning so we moved it to dryer spot in yard. It struggled through winter and then had some green leaves again. I thought we made it. Now I have black spots and then leaves turning brown. What can I do? Please help.