Fizzing temperatures are expected to hit southern Colorado by the end of the week, posing a risk to plants that have already begun to leaf out. New growth is the most vulnerable during a sudden freeze, according to Levi Heidrich, part-owner of Heidrovsky's Colorado Tree Farm Nursery. Vegetable and annuals are particularly at risk, with plants still in containers being brought indoors to avoid exposure to freezing temperatures. Watering these plants ahead of the cold snap can improve their ability to withstand freezing conditions, and avoiding heavy coverings could cause damage if weighed down by snow.