Have you got a sun porch, sunny vestibule, or garage that you can supply with minimal heat? Grow lights and well-managed cold frames will also work.

The tuberous sages like guaranitica can be kept in cool and dark locations that don't experience cold below 25 degrees. However, when they break dormancy, they will need sun and minimal temperatures of 35 degrees.

My basement during winter is at 50-60F. Is that fine for keeping them dormant? Garage is definitely impossible since I've seen water bottles start to freeze around December. Our peak winter is middle January until early February.

In my breakfast room, we get sunlight there starting 1pm until 4-5pm. Will that work?