Answer: The tree you purchased will make a striking addition to your landscape. Although it is slow-growing, it can eventually reach 40' in height, with branches spreading 15-20' out. You can control the size by cutting the new growth halfway back in late spring but I'm afraid it will grow much too large for the area you describe, even if you prune it back every year.
I hope you can find another place in your yard for your new cedar - a site where it can grow without pruning, becoming the bold focal point and commanding the attention it deserves.
Best wishes with your garden!
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