These iris' have been in the family for 100+ years. My family has never grown any other variety and my neighbors don't own any either. These were originally planted in the Texas Panhandle. When my great grand mother passed away, my grandmother transplanted them into her flowerbed, also in the panhandle. When my grandparents passed away my mom retrieved most of the bulbs and brought them to DFW. They did very well and bloomed their normal light purple for two years. Then in 2018 they bloomed purple, and later that same year they turned orange. This year there are no purple blooms, just orange.
We haven't used chemicals around them. The ones in the pictures haven't been moved or cut back since we got them. I did move the ones in the front of the house to the other side before they started blooming. Only one stalk lasted and it's also orange. Those are not shown in the pictures.
Everything I've read about these changing colors has to do with different varieties taking over or cross pollination so I'm posting this to maybe get a few more suggestions or see if anyone else has this problem and knows how to fix it, because we really want the original color back.