No need to trim leaves at all unless they don't look healthy.

Only dug rhizomes should be trimmed before re-planting.

They will grow into a fan shape all on their own. You can trim off yellowed or brown foliage if it bothers you.
Renee

By the way, bearded irises generally hate mulch, and they often get rot when mulched. You may want to clear away the leaves from yours.
Renee

I take a household scissors and trim the dead part off flopped-over leaves. For totally dead leaves, you can usually give thema sharp tug and they will come off at the base---be sure they are all the way dead, though--you don't want to yank the plant out of the ground!

When leaves flop like some in your photo have, it is usually a matter of time before they get a crease & the flopped part dies off anyway. I don't like to leave dead parts on plants because they attract bugs whose job it is to return plant material to the soil--- and I don't see a need to attract plant eating bugs!

Pull away the mulch -- irises want their "feet" out in the sun! And the mulch will harbor more of those root-eaters.

Another suggestioon -- your irises are way too close to each other. If they are happy in your garden, they will make clumps this year and get very crowded. You don't have to move them farther apart right now, but be aware when they get larger you are going to have to give them more space!

Thankyou everyone! A little too close together huh? OK, I guess in August would be a great time to move apart? That's usually the time for planting iris rhizomes here in zone 5.

I did remove the mulch from around the irises today. I only put it on last fall when winter was setting in. The rest of the time they go without.

Cheers
Cathy