No! It won't kill them but it would help to know what type of banana you're growing.
When you dig them up, dig deep to get plenty of roots. Get the plants inside quickly as possible and near a warm spot in your house.
1. Wash all the dirt off the roots & corm.
2. If any part of the plant is soft & squishy (spongy), cut those parts off.
3. Dry it off gently with absorbant paper towels.
4. Put what's left (after cutting off the soft parts) somewhere dark. Exposure to light, while the plant is warm, can cause it to come out of dormancy.
5. Leave them stored at less than 55 degrees F for the winter & replant them in the spring.
It always takes a few weeks for the plants to start growing new stem & leaves in the spring so be patient. Please keep us posted on your progress. Ask any new questions you need to ask.
Now, Welcome aboard, Lisa, from Oklahoma

! It's a very friendly & info-packed site. If you have any questions about using the forum, just ask!