From what I heard, Las Vegas had a couple of cold snaps. At The Orchard in North Las Vegas the low temperatures hit 16F at 4:30 am on February 15th while the high was 46F. Freezing weather can take several different twists depending on a few things.
First of all, if there is a warming trend during the cold winter months this can really mess things up for the plants. They think it’s spring, let down their winter guard and wham… it freezes and they are taken by surprise and they sustain more damage than they would if it had gotten colder more gradually.
If damage occurred to your plants and you can tolerate looking at them in that condition, then let them go until you see growth in a couple of months. The presence of vigorous new growth will tell you where to prune and whether the plant was killed, or just looks like it, but it isn’t. I will post more about winter freeze plant damage on my blog this week.