Texas is notorious for having late freezes; and that is your enemy. The root system is now well established so if the plant dies back a little; it will still survive.

Where exactly are your trees-- north, east, west, or south side of your house? Are you in the northern or western part of zone 7? How long has it been since they last froze? My Wonderful pomegranate seems to fruit on wood at least two years old. Thank you.
I'm on the south side of dfw. My Wonderful pomegranate is planted 10 to 15 feet south of the south side of the house in the fenced in back yard, so a protected area. It has been in the ground for 10-15 years. When it was about 3 years old, it froze back to the ground once or twice, but nothing has phazed the tree since then.

The birds decided the green fruit was good in the drought a couple of years back and have kept coming back for more. This year I will put on bird netting before they get started.

I was able to overwinter a dwarf pomegranate in a sheltered area in zone 5 with a thick mulch. Despite some freeze damage, I had flowers on the bush the next season. For the following winter, I dug the plant and brought into the house and killed it.