Low was -28, only 1° from my coldest Feb morning here. That came in 2003, the winter that killed my peach tree. Planted in late May 1998, that Reliance peach would grow vigorously in summer then die back to about 2' tall each winter. Then 01-02 didn't get colder than -12, there was no dieback, and the tree produced 100+ luscious tennis-ball-sized fruit. Jan-Feb-Mar 2003 reached -20 or colder 12 times, bottoming out with that -29 in Feb, and it was lights out. A weak sprout came from below the graft, thus useless, but it died in July anyway.