Thanks for all the replys. So glad I came across this site. I live in Montgomery Alabama and yes, we had a very cold winter. We even had a dusting
of snow one day. The plant in question is a Katrina African Iris. It is a beautiful fast growing plant. I bought it in Baton Rouge Louisiana where my daughter lives. They are everywhere. I have been told to split the plant up around 3-4 yrs of age.
I am going to try and cut the brown foliage off and hopefully it will recover. Yes it is southern clay with a lot other soil, and very good drainage.
Happy planting!