Was wondering if anyone has ever grown a Clethra ainifolia/Summersweet "16 Candles" in a container?

Could we overwinter it outside in a container? Mid Atlantic region, Zone 6b. Average low winter temperature generally doesn't ever get below 20 degrees F.

If it's OK to overwinter in a container outside, is it better to place the container in eastern exposure/part shade for the summer and then move the container for the winter, so that it gets outdoor southern exposure/full sun during the winter? Or should we just leave it in eastern exposure/part shade?

Or, is it better to overwinter indoors? If so, is southern exposure indoors too much sun for it in winter?

Also, has anyone ever given a small Clethra like "16 Candles" any Holly-tone plant food?

Any suggestions or experiences with Clethra would be appreciated! Thank you.