Hey Dogtown- just a couple things to consider:
-Make sure they're getting enough sun, as well as water (usually during the first growing year, the soil should stay moist pretty much all the time)
-Don't plant too many in one container. Their root balls will get HUGE, and they will spread all over the place, but won't produce well if they're all crammed in there.
-I think I heard somewhere you're supposed to grow the same hops in one container together (at least, that's what I've done).
-Sometimes, rhizomes won't grow for whatever reason -- so you may find by the end of this season that that one rhizome just didn't do anything. Personally, I'd leave it where it is for at least this year, just to see if it's a "late bloomer" (but maybe that's stupid advice on my part -- I did that last year and the dang thing never grew).
-Hops really appreciate fertilizers like fish emulsion -- may want to pick up some of that, too.
Check the archives for the episode they did a few months ago on growing your own hops; that may answer your questions (and perhaps be more factual than my two cents here).
Cheers!
Kim