In 1989 the temperature here dropped to 14F and there was no cold damage to our fig tree. I believe it was a celeste fig. Celeste figs are hardy to at least 14 F and probably for short durations near 0F! In ground fig trees are common in zone 8 and 9 and should survive zone 7 winters and possibly zone 6 with some protection.

Celeste fig is an extremely cold tolerant plant!