Here's a close-up of Chamaecyparis lawsoniana 'Blue Surprise'

https://www.google.ca/search?q...

Finally we have an ID from Longwood:

"That plant is Chamaecyparis lawsoniana cv. Blue Surprise. It’s a Port Orford Cedar native to coastal northern California and Oregon. This plant is not well suited/long lived in the mid-Atlantic region."

So Sue @sooby had the correct ID.

Thanks to all for your suggestions.