I have grown at least 10 species of Chamaecyparis in containers of all sizes, and all have performed exceptionally well. I think it's a good choice as a container tree in general, but lawsoniana will need lots of winter protection in your zone. It NEEDS full sun for the best color. You might need to shade the container to keep soil temps down, too.

Al

Thank you Al. I potted up three of them to screen my patio and they look beautiful. Question: what sort of winter protection will I need to do?

Over winter ...... container buried against the fondation on the north side of a heated building or just leave it rest on the floor of your garage, but don't forget & leave the o/h door open for extended periods when it's below 20*

Al

Al, should I bring them into the garage now? I didn't want to bring them in too early, but we are starting to get some cold weather now. Also, when can I bring them back out in the spring?

Yes, it's about time to bring them in - mine are in the garage already. I put (most of) my temperate plants back on the benches when there is little danger of night temps dropping much below 27*. If lower temperatures are predicted (down to about 22*), I make sure they are setting directly on the ground, not on a deck or railing so they are isolated from the warmth of the earth. I try not to expose them to anything below 22*, even if they are on the ground.

Al