It got down to 0 degrees F three times at my house this winter, where it stayed zero all night long. It did of get much above freezing if at all the whole month of January. I remember days when the highs got into low twenties and thought we were having a heat wave. The only citrus that survived at my house this winter were the ones with the plastic covers and space heaters. All my poncyrus by rides died, even though they were buried in leaf cages with buckets of water and covered in frost cloth and had plastic wall wind breaks. The only hybrid to survive was Thomasville citrangquat which is now putting out a sprout from base of tree.