I pulled roughly 3 months once (fresh cuts in a ziplock, and when I planted them, they rooted like mofo's.. They didn't look that pretty when they were rooting, but they became vigorous plants.. Questionably the most vigorous I ever had off that mother.. 9/9 rooted IIRC, (all I remember stats wise is that 100% rooted however many I had)..
Edit: Just don't let them freeze.. 32-35°F (0-2°C) perhaps.. I had a really stable temp where I kept them, at about 0.3°C.. The freezing point of green plant material is actually slightly lower than pure water due to impurities..