Note: that all petals in this clump of plants are evenly balanced, and evenly spaced. (none are crookedly spaced). And this is consistent with this iris plant. For me it didn't happen just one year. It may have been something in our soil that I'm not aware of, but none-the-less this is the only plant that has done this for me, year after year. ( I personally no longer grow it due to space) I understand it hasn't done this for many growers, but for some it has. if I knew what causes this to happen I would replicate it, (and share that info) but I really don't. It may have just been a fluke of nature. As you can see...even if it doesn't put out the 4-4-4 on it's terminal bloom....it's still quite showy.