Here in Michigan, we clean up all weeds and add a fresh layer of leaf compost. We sidedress the rows with a shot of potassium (which acts like antifreeze in the root system). Avoid applications of nitrogen fert. now to avoid blowing out the crown buds that are setting for next spring. All our containers /pots are grouped, mulched over and covered with a frost cloth. We put mouse bait under the cover to keep the vole population down. All drip emitter lines are throughly blown out, so they don't pop apart when it freezes. Our big containers are heeled in (buried) about halfway and mulched over, also.
We used to split crowns in the Spring, but we have started doing this this in late fall because the weather is more predictable and the crowns seem to prefer it. (As do our seasonal help!)