Hmmm. If you have it in a pot or bag maybe put it in a styrofoam cooler and fill with mulch around it to keep the roots protected? I can’t remember who posted it above but building a hot house to cover it would help. Maybe put it close to your dryer’s outdoor vent area? Heat bricks in the oven and put them in the hot house? Locate them where they will get southern exposure?
@Backmoon kept clones alive one winter without heat.