Lori, wonderful collection of historics!
Sherry, I'm seeing a dramatic example of how soil and location can effect colors. I moved some Amas to the base of this silver maple where almost nothing else will grow, and forgot and left one rhizome sitting in the gravel next to the bed, where it rooted and is blooming happily. The one in mostly gravel is blooming normally, but those behind it in the bed are much paler in color.
In this first photo, you can see both, next just the lighter blooms.