@luis_pr 
Thank you for taking the time to write such a thorough and clear response to my question. I am very disappointed because all 4 hydrangeas I have are infected. I had purchased 1 hydrangea at home Depot last summer and immediately rooted it into 3 other plants for a total of 4 plants. I planted the main plant that I had purchased and I left the other 3 protected over the Winter to grow in their pots. All 4 have the spots this summer and I am wondering if it's just best to throw them away. The purplish discoloration is so pronounced and ghastly - just awful. I had already thrown away the worst leaves when I found the small one that I used as a picture in this post.
So I guess I will have to be regimented about Spring the hydrangea that is planted. But, when I eventually sell the house I will need to dig up the one that I planted and throw it away as well? Or, should I just dig it up now while it is still small and replace it?
Thank you again for your assistance, I truly appreciate your help. Terri
