My garden has been hit with powdery mildew. I first noticed it on some cucumber plant leaves. It started as a few white fuzzy spots on the leaves. Within a few days the entire vine was a white fuzzy vine. I had to pull out several pickling cucumber plants. I will not be planting any sort of "compact" or "space-master" plants next season. I found that because the plants were designed to be so compact the leaves really crowded each other and caused poor air circulation. This invited the powdery mildew in. This stuff spread to my squash plants and it's all so close together that before I knew it just about every squash plant is infected. This mildew is bad news bears because the mildew grows on the leaf and spreads and blocks out sunlight. This slows and eventually stops photosynthesis. If the plant can't get the nutrients it needs to grow the fruit then you will have small fruit and no new blooms which is exactly what started happening to me. I read that a baking soda mixture sprayed on the leaves will help reduce the mildew so I went ahead sprayed the plants but that didn't help. I did more research and read that spraying milk mixed with water on the top and bottom of leaves is helpful. So I went out and sprayed my squash plants with watered down milk in 90 degree weather which was pretty gross. However, the milk seems to have arrested any further growth of the mildew. I clipped the leaves that had the majority of it covered in mildew. I also pulled out some plants that were crowding the other plants in order to improve air circulation. The mildew isn't gone but it isn't getting worse. I may need to do another treatment with the milk. I'll keep you posted.