Q.Overwintering annuals
Hi -live in Sisters, OR, gets below 0. Can I put the Joseph Coat Verbena that I grow all summer in pot, cut back and dig in or better can it be overwintered in pot in garage? I grow them in big pots all summer but the first frost they die. These are the verbena that have woody stems. Any ideas? I also have a sun room with a heater. Thanks so much.

Certified GKH Gardening Expert
This species is actually Alternanthera. They are only hardy in zones 10 and 11. They do not have a dormancy, so they will have to continue growing in spring.
I believe the best option for you will be to grow these in container, then bring them in during the winter to let them keep growing in a bright locations.
This article will give you more information on the care of these: https://www.gardeningknowhow.com/houseplants/bromeliad/getting-bromeliads-to-bloom.htm