If this is a hybrid then you might have more than half come true with a variety of other colors. I'm just basing this on impatiens we used to let come up year after year. They started out almost true to the salmon color we had used for 2 to 3 colors from the nursery. As the years went by, it became more a mix of white, red, orange, pink, and salmon. Maybe if we had removed the other colors starting at year one, then we may have had more luck at keeping it fairly true.