Late summer pruning Sisyrinchium striatum?

Just realised that I didn't tell you what plant I am talking about! Its Sisyrinchium striatum. ( I thought it was a site dedicated to just this plant for some reason!)

Thanks

I just cut out the flower stems and pull off the black leaves to tidy the plants up. Sometimes I take off a fan or two if they are getting a bit crowded, and plant them up elsewhere or in a pot for a friend!

Thank you Spritzhenry, just as I thought. I wonder why Iris is dealt with differently? I must admit it does look better with some leaves left on the plant rather than scalping it!