Yes, they'd grow after the last frost, but you probably won't find rhizomes as early as February. Most of the hops growers trim their crowns in the spring, and for some places, spring is as late as May (like me). I think commercial sellers sell them in March/April usually.
I plant actual plants instead of rhizomes and I'm in south central Ohio. I planted May 10 last year and weathered out one really light frost that had no affect. I'll probably plant around the 17 though this year just to be safer.