Outdoor flower pots and containers require proper winterization in order to survive the cold months. The soil in a flower pot is more exposed to wind and other winter elements than garden beds, so perennial plants are more likely to be damaged while dormant. Even if no plants are in the pots, the pots themselves may suffer winter damage. Prepare the flower pots in late fall before the soil begins to freeze to ensure both the pots and the plants inside survive until next spring.
Dig up the roots or rhizomes of tender perennial container flowers such as begonia. Store the plants inside perforated plastic bags filled with dry peat moss in a 40-degree-F location until spring replanting.
Dump out the old potting soil from flower pots that had annuals and tender perennials in them. Place the soil into the compost pile.
Cover the soil in pots housing hardy perennials with a 2- to 3-inch layer of organic mulch. Use wood chips, bark or straw. Mulching preserves moisture in winter and helps prevent root freeze.
Move plants to a greenhouse, shed or garage to protect them from extreme winter cold and wind if possible. Alternately, move the flower pots to the side of a building or fence that is protected from heavy winds.
Turn empty pots upside down or place them in a covered area so they do not collect snow or water during winter. Standing water in pots may freeze, leading to cracked flower pots.