When can IRIS be cut back?
Thereof, should I cut back irises after flowering?
After blooming is finished, cut flower stems down at their base. But do NOT trim iris leaves after they have finished blooming. Leaves carry on photosynthesis for next year's growth. Cut off brown tips—and cut the flowering stalk down to the rhizome to discourage rot.
Regarding this, how do I get my iris to bloom again?
Remove rhizomes from the soil carefully with a garden fork and divide them with a sharp, clean knife so each new section has one to three leaf fans and healthy roots. Replant immediately. Most irises prefer well-draining soil in a sunny location. Your irises should produce more blooms the next year.
Deadheading, or removing the old flowers, keeps the plants attractive and allows the leaves to collect energy for healthy root formation instead of setting seeds. Some irises may bloom twice a year if you deadhead properly. Break off the individual flowers on each flowering stem after they finish blooming.