Answer: Winter protection can mean many different things. Primarily, it is to reduce exposure of the plant to the drying effects of wind and sun during the winter season.
You can accomplish this task in a number of ways. Quite often, burlap is used to create a physical barrier against the wind, either by wrapping the plants individually or creating a "wall" of burlap. Personally, I don't like the visual effect of burlap, but it does have its purpose.
Another way is to use an anti-dessicant/anti-transpirant. These are chemicals that are sprayed onto the plant in fall to reduce the amount of moisture the plant will lose through its needles.
By reducing the amount of moisture a plant loses, you reduce the amount of moisture it requires. They also help to reduce the amount of de-icing salt that may come in contact with the needles, which can burn them.
I prefer this method over the burlap because it still allows the plant to "breathe" as it were, and also get sun during the winter. If your spruces will be in a very windy area, however, you might combine these 2 methods as extra protection.
Also, be sure to water them well before winter, and even during the winter if you have periods of low precipitation.
One of the causes of "winter-burn" is due to lack of soil moisture, so you want to be sure that your spruces have adequate moisture available to them when they need it.
Aim for one-inch of water per week during summer and fall. Water periodically during the winter months if the ground is not frozen.
Best wishes with your spruces!
Q&A Library Searching Tips