Has anyone had luck transplanting very mature ivy?

I uprooted a very mature piece of ivy yesterday and am wanting it to grow vertically (from my planter to the trellis on my ceiling) on my back deck. The ivy may be around 15' long and I'm afraid it's just too old and long to try to transplant. Anyway, my question for you guys is in regard to the exposed tenticles (approx. 1') of the original root system (after at least that much was buried). I've added a root stimulator and fertilizer, but am wondering if I need to clip some of the original root off due to it's length, mist the exposed tenticles every day (it's 100 degrees here) or what?!! Many, many thanks!!!