I don’t know why this is the first year I have seen twin buds in my Iris cristata, but I have many, many with twin buds, in a couple of different spots; it’s especially obvious now that they are fading. Maybe they are sports. Maybe it’s the unusually dry weather. Maybe they’ve been there all along, and somehow I’ve missed them. I will be watching the area more closely over the next couple of years.
The entire Iris cristata population of my yard is descended from two purchased potted plants. I planted the first pot in a likely looking spot, and they disappeared. They did not come up the following spring either, so I bought another pot and chose a different spot. They disappeared too!
The following spring, both plantings reappeared. Once they got established, they do not normally lose their foliage in this yard until late October. They bloom and then remain a tidy groundcover for the remainder of the growing season.
The swath planted near the pawpaw at the eastern end has since swept around to form two arcs around this flower bed. It is two arcs only because I put a pathway through the middle of the bed for easier plant access. The eastern pawpaw was removed at the beginning of April (2021). While I did move some plants around, most of the work was done by the Iris cristata. The trunk that you see in this photograph is of the western pawpaw, which is ringed by twinleaf.
Are all these Iris cristata clones? I don’t really know. I suspect most of them are. I have never seen an obvious seedpod, and the irises that I have seen make obvious pods. If I can spot twinleaf seedpods, it seems unlikely that I would miss these.
The answer to the twinning question may become obvious over the next few years, or it may turn out to be a quirk. Time will tell.