Answer: The answer to your question depends on a number of factors. Assuming you have varieties rated hardy in your zone and they have several inches of mulch over their root zones, and that they are well watered up until the ground freezes, then the protection becomes a question of heavy snow, wind exposure, and sun. If you often have heavy snow you might be prepared to knock it off of them before they break under its weight. If they are in a windy or full sun location you might want to apply an antidessicant spray to reduce moisture loss through transpiration -- this can help the foliage (and the plant) come through in better shape. You could also erect a wind break for the first few years until the plants are well established. In my experience, wrapping plants in burlap creates an unsightly situation and prevents us from appreciating the evergreen qualities of the plants so I would suggest the other measures first.
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