What year to I start cutting back?

Okay, so last year i planted 75 rhizomes or 5 different variations. Alot of the rhizomes i got in the ground a little late into the growing season cause it was a last minute decision. Alot of them didnt produce/yield much growth above ground. Some barely breaking the surface. I just checked on them and dig a few up to see how they are doing and they seem to have survived the harsh winter and have established a good root structure. I know they suggest cutting back the rhizomes to prevent them from growing rampant. My question is, is before the second year too early to start trimming back? And if it is when is it proper to start cutting these back and transplanting some rhizomes?

Too soon. Let them get to 3rd or 4th year before disturbing them. You might also just dig in a circle around them about 2 ft from center every other year or so after that.