Irises

I do not know if cutting the leaves back is required. However I like to cut my iris leaves back in the fall to about 4 inches as the leaves tend to get brown anyway. By doing this it airs out the plant and prevents rotting around the rhizomes as well as providing less cover for slugs . There is less cleanup in the spring as well.

I don't cut back the leaves unless I am lifiting and dividing them. However I do pull off all the dead leaves (which come away from the rhizome quite cleanly)