Answer: Alberta spruce trees rarely need pruning. Their natural shape is conical, and since they only grow 2-4" per year, they don't get out of shape very quickly.
If you need to prune them, only snip off a little bit If you prune too far back you'll prune into non-productive tissue, and a bare spot may result. Bare spots almost never fill in on an Alberta spruce, so be careful along these lines.
I would basically just leave them unpruned. As they broaden at the base over time, enlarge the landscape bed they're in to accommodate growth instead of pruning back. This will develop a nicely-shaped tree over time, with very little need for maintenance on your part.
That being said, you can painlessly (to the tree) slow down the growth rate of a spruce by removing up to one half of the "candle" that forms in the spring. The candle is the elongation of the branch end, from which the needles emerge. It's best to wait until the candles are as close to fully elongated as possible but before the needles unfurl.
Best wishes with your landscape!
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