If they're sun-bleached or damaged, I cut off the "burned-up" parts, but that's all;

I don't think any healthy iris growing in the ground should ever have its green leaves cut.

Firstly, they need those leaves for photosynthesis, so they can feed energy to the rhizome for next year's bloom & for the making of daughter rhizomes.

Secondly, in our Southern zones, irises are evergreen, & the regular leaves are beautiful, while the chopped-off ones are...not-
but if it's a choice between chopped-off & burned-up, I'd choose chopped-off.

Hi Sylviatexas, thanks for your response. It is mostly the outher leaves that are turning brown on the tips. Some of the other leaves have brown spots, but that doesn't bother me that much. I guess I'll just cut the brown part off and see how it looks.

What is your fertilizer schedule like? Here in Las Cruces we are having 100 degree afternoons. The iris that I planted last year with 1 tablespoon of super phosphate and 1 tablespoon of 14-14-14 time release fertilizer in the planting hole show little or no browning of the tips. The old clumps that should be divided this year are showing more tip browning. My theory is that the new fans are taking nitrogen from the old leaves. In past years, I had tip buring from too much watering accompanied by rot. My fertilizing schedule is at planting(see above), 9-52-9 foliar spray 6 weeks before bloom, and 14-14-14 time release following bloom. I lift, separate and share rhizomes every 3 years because my sandy soil needs the superphospate and compost.

Kristee