Pink Hardy Hibiscus

Several years ago I bought 2 hardy hibiscus at the same time. One white and one a VERY dark red. Thought they would look great next to each other. Apparently in the hibiscus family the white is the dominant color. The red soon turned white. They are now planted 150 ft from each other and the red has now turned back to the above color. Maybe when I bought it they had put food coloring in the water, or maybe it just can't get back to it's original color. At least it has turned back to pink, and I do like the color. I like the fact that daylilies and iris don't bleed over like that, they can be planted right next to each other. I didn't know about the hibiscus, but we live and learn.