Answer: The overall shape of the Canadale will be more mounding rather than upright, unless you prune it. The mature size is listed as 4 feet tall and about 3 feet wide. This would mean you could leave it untrimmed if you wish and have it hit the desired height. At 12 feet tall and 6 feet wide, the Chollipo is an overall much larger plant and would require regular pruning to keep it in bounds if you planted it at the spacing normally suggested for the much smaller Canadale. Generally speaking it is better to plant something that matures to the desired size rather than requires ongoing pruning work to be kept the desired size. Also, I should mention there is a winter hardiness factor. The Canadale is much more cold tolerant than the Chollipo. This means it is less likely to suffer winter stress and should also hold its foliage better with less winter burn than the Chollipo in your zone 6 location. You could consider planting a vine on the fence behind the shrubs as a way to soften it, just a thought. I hope this helps.
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