This iris is a new addition to my garden this year. When we got it, we thought it was a deep blue, but when it bloomed this year, it is a deep velvety purple. My husband thinks the acidity in the soil caused the blooms to change color. I have never heard of that with iris, have you?? I know that hydrangeas change their color depending on the acidity of the soil. I hope you are enjoying sharing my garden with me.