How do you get rid of mildew on the summer phlox? I have tried cutting back and returns when plant grows again. I try to keep space around for air circulation - but does not help.

Unfortunately, many cultivars of summer phlox are prone to mildew. Thinning them out to increase air circulation can help, and watering the base and not the foilage may help. You can also try one of several commercial fungicides. I would reccomend planting in the future only mildew resistent varieties, such as 'David.'