Is the Atlanta Botanical Garden opened in winter? If so, what is there to do this time of a year?

Just a little curious... I've been to the Atlanta Botanical Garden in the summer and most of the exhibit I encountered then was outside... In winter (when most plants die) what can you do at the Atlanta Botanical Garden? How is it there during the colder months? I'm thinking about going.. but I don't know what to expect. Thanks for your help!!