I have some cherry tomato plants that were doing very well indoors with grow lights, but I had to move them onto my balcony in late June. A couple weeks later they began developing a white growth over the stems and leaves. I did some research and came across powdery mildew, but several sources say that it only grows on leaves. I went ahead and got GardenSafe Fungicide3 spray, which has the active ingredient extract of neem oil. I sprayed pretty heavily a couple weeks ago and within a couple days, all the leaves began wilting and dying. I have seen growth of some new leaves though. There was still some white growth as of tonight and I just did another light spray. Does anybody have any suggestions? Thanks in advance.