over wintering citrus tree in Arkansas

I live in central Arkansas.  Some time ago, herard a topic on local radio gardening call -in.  People who had successfully found a orange tree that over wintered, outside, in northern Arkansas.  To that end I've had a citrus plant grown from seed that after many years of being in a pot; put outside in summer & brought in in winter, grew to be abt 3' tall. So planted outside & mulched heavily. Anyway top was all dead (all 3') after mulch removed in Spring.  But, but - after 6 weeks noticed new growth from bottom 3 inches of stem.  Clipped off all dead wood above, and let "sprout" grow.  Now, today this growth and others are four feet  tall! Ok, what do I do?  Will this plant behave like hardy-hybiscuis; die back in winter and regrow in spring?  Never having long enough season to bear fruit? Should I mulch again and hope for mild winter for regrowth to begin farther up tree to maybe have blossoms? Orginal radio show mentioned type of orange tree that does survive winters.

Part 2: my citrus is evergreen & has large thorns - what kind of plant is this?  Orange, lemon, grapefruit?  Clipped/rubbed leaves have strong citrus odor.

Any ideas or advice appreciated.