Hugging The Ground, and Hanging In There

We have been having light freezes every night for a couple of weeks. However, a ground cover annual called verbena continues to flourish in the bright Colorado sunshine. I guess it doesn't freeze because it hugs the ground. The annuals that grow up higher in the air are gone. Come to think of it, the calendula is still blooming, too. I'll try to remember to get a picture of calendula tomorrow.