You can't wait for a bus on a Saskatoon street during a record-cold January day without giving at least cursory consideration to the issue of winter survival. The strategies of winter survival can be summarized as either avoidance or tolerance. In the human world, the difference between winter avoiders and winter tolerators is usually financial - the option of avoiding winter is typically only available to those who can afford it. Sure, these people may stick around long enough to videotape the grandchildren's Christmas, but the very next day they aim the car toward Arizona and set off as fast as road conditions allow. For those of us who cannot afford this agreeable luxury, tolerance is the only option.
Plants are also divided into avoiders and tolerators.
Annual plants take winter avoidance to an extreme. They rush through summer in a desperate attempt to set seeds before winter's arrival. In fall they promptly surrender to a frosty night - dying and leaving only their seeds to represent them the following year. Seeds of even the tenderest annuals will usually survive winter if they are fully ripe and dry. This is because the single most important aspect of any plant surviving winter is its ability to prevent ice from forming inside its cells.