I have half a dozen Loropetalums, (garnet fire). They are two years old. A...
Loropetalums are marginally hardy here. Last winter was too cold for them. The only thing we suggest is to prune out any dead areas and make sure that they do not undergo any additional stress, for instance offer them additional water if we were to enter a period of drought this summer.
They also could benefit from a 1-2 inch layer of mulch (keep it off the trunks). You could increase mulch cover in late fall to offer some winter protection to the roots, but the extra mulch should be removed the following spring.