WHEN DO I PRUNE SAPPHIRE SURF BLUEBEARD, AND HOW FAR DOWN DO I PRUNE?

Caryopteris is a little bit tricky when trying to figure out how much to prune! I would definitely wait until late spring when it starts to leaf out. Depending on cold the winter is in your area, it could dieback close to the ground. When the leaves come out, you will know the answer. In the spring, first trim off any dead branches. Then, trim back any dead tops. Be sure to mulch it well this winter.