One extra tip-off for Immortality is when it's still in "bud", with just a small amount of color showing, it appears the flower will be light blue. But, of course, when it opens, it's white! There are quite a few white iris that seem to show this trait, but, if it re blooms,(and hasn't got the "best' form), that narrows the field a lot! Just Immortality, and I Do. Immortality is by far the most "popular of he two...Arlyn
