I decided to box up a 6x10' section of my garden and heat it to 40 degrees for last winter.  Things didn't go so well.
 
		Bougainvillea 'Bengal Orange' - dead
	
	
		Red Abyssinian Banana - dead
	
	
		Blue Java Banana - dead
	
	
		Castor Beans - dead
	
	
		Acalypha - dead
	
	
		Thailand giant elephant ear - dead
	
	
		Gardenia - alive, but defoliated by mites
	
	
		Trachelospermum jasminoides - alive and well
	
	No idea what happened.  I haven't dug them up yet so maybe I'll find underground rodent damage.
 
	Misc: hard to believe that if I had covered the windmill palm for that night of -16 two winters ago, it would have sailed through this winter with ease too.