David, I would either put them in a greenhouse, or hoop house. I'm in 8b and the only gingers I've lost have been left in ground over winter. If you can put them in pots and keep them until the weather warms you may see blooms this coming summer.
The turmeric can be dug and left to dry. You can replant it in spring, or use it and buy another
rhizome. You may just keep it in a pot indoors and set it out when the weather warms a bit. It takes a bit to see them flower. Some years I don't see any blooms. Sometimes only one plant will throw a bloom.
http://garden.org/ideas/view/B...
