Hi Elizabeth,
I am afraid that without some type of protction that fig trees in our area would freeze back at least to the ground and in a prolonged cold spell possibly even kill the roots. I have seen daytime temps in the -25F range (not just wind chill). Thats why we bury our water lines 36 inches deep, to keep them below the frost line. Our house is just east of downtown KC, in part of the old Italian area, so we usually have some heat island effect to help a little and that also seems to cause some of the storms coming from the west to split and go around us. The HC that I plan on getting planted in ground will have to be mulched and then a cage around it filled with dry leaves or some sort of other insulation, then wrap the cage with either a blanket or carpeting (so as not to trap too much moisture). Will most likely still have some frost damage but hopefully it will be lessened. If the damage is minimal then as the tree matures and grows stronger it should less suseptable to damage on the main parts. I know that in the town my wife is from, just south of Pittsburgh PA, their weather patterns seem to be similar to ours, so much so that her sister calls up to see what weather we are having so she knows what to expect a couple of days later. Her neighbors dad had a fig tree in his back yard that was never covered or protected, big tree and most likely a brown turkey, that would be full of figs every year. Guess if you can get them to a mature enough size and have them planted where there is some natural protection (south side of a house or stone wall) then there is a better chance.
No matter where folks try to grow them there seems to be unique obstacles to overcome, that is except for Jon and his prime "fig heaven"! ;-)
Woody.