A:  This is certainly the time of year to do it - late winter/early spring, just as buds break dormancy, is when one should prune roses.  But with Knock Outs, pruning should wait until the 2nd season of growth (some say its best to wait until even the 3rd season). Knock Outs are designed to grow vigorously, so prune them down to about two feet below the height you want them to reach during the growing season.

For more information and other suggested resources about pruning Knockout and other roses, check out this article written by Karen Neill & Guilford County Cooperative Extension, http://guilford.ces.ncsu.edu/2013/02/200515/.

A:  It's not necessary to dig them up as they overwinter quite well here in the Piedmont.

A:  It may be time to divide them.  Also make sure that you allow the foliage to die back naturally for next years bulb development.