Many homes have patios and decks complete with large pots containing shrubs or trees.
These containers provide a feeling of permanence and beauty to the area. Unfortunately for those of us in Iowa, containerized plants often experience severe winter injury and often death if unprotected. In containers, the roots of the plants are exposed to below-freezing temperatures on all sides. As temperatures fluctuate, the soil thaws and refreezes causing the plant to heave out of the soil. This tears the roots and can expose the roots to drying winds.