Just something I discovered in my rot search the other day: Bloomstalks that are not snapped or cut to the bottom after blooming are quite likely to rot, as mentioned in this forum. However, those that have formed bee pods (many this year) are quite firm. Do you think this might be good to do in a wet year? I imagine growing a seed pod would take energy from the plant though, and maybe not worth it in the long run?
Last year I planted iris in a new spot that had a lot of compost on it, and there is much less rot than in my main bed. It seems that frequent division is a key.

Any time that I've had a disease problem, it was always in crowded beds. I think good airflow, and sun light are the 2 best things we can do....Arlyn

I have had stems rot off while there were blooms on it. I've also had crown mold on newly replanted rhizomes (just planted the year before) and I have had seed pods lost to a stem that rotted off. I had one plant that for the first two years, every bloom stem rotted off, then finally the 3rd and 4th year there was no problem. I also have had mold begin in the mid section of the stalk, and the top half falls off. I have one iris, My purple seedling, that is near a leaky eve's trough, and gets saturated and sometimes is under water, and it's never had a problem with mold. I've had plants next to one another where one gets it , and the others around it aren't bothered. I have lots of unanswered questions about it. I also think that there may be more then one type of mold or bacteria causing it. I have no evidence of this, only a speculation. I'll bet Kent has some information on this.

So much for my theory!