Q: I would like to relocate an Alberta spruce tree. When is the best time to do that?

A: I would move an Alberta spruce prior to bud break in spring, or if it's already beginning to grow, I would wait until late summer/early fall.

Once the plant begins to grow, it's depending greatly on the root system to provide the water it needs. Digging a plant removes a large portion of the root system (some estimates are up to 90%!), which shocks the plant and reduces its ability to sustain itself.

However, if you must move it, over-size the root ball you dig as much as possible (to get as many roots as possible). I would still be prepared for some consequences, though (drying back of tips, perhaps more).

But, if it's a small plant, you may have no ill effects whatsoever if you really over-size the ball and water thoroughly.

Water thoroughly 2-3 days BEFORE digging the plant. This will get the crown as moist as possible before it gets its roots chopped off.

Water thoroughly once a week AFTER. Keep in mind that the roots are what get the water to the crown, and you've just cut off a lot of them to move the plant.

So, although watering is the thing to do, the crown may not get the water because there are fewer roots to supply it.

You might also apply an anti-transpirant to reduce the amount of moisture the plant will lose through its needles (which helps reduce its need for water).
Good luck!