How to Prevent Cracks in Terra Cotta Pots
A crackpot in the garden is one thing, but nobody wants cracked pots. Don't let the weather damage or ruin your terra cotta containers.
When the temperatures start dropping, it’s time to protect your plants. Houseplants that spent the summer outdoors need to be moved to warmer quarters before the first frost, while tender bulbs should be dug up and stored. Some edibles can last a little longer if they're sheltered under old blankets, tarps or row covers.
But while we’re saving the green in our gardens, it’s easy to forget another valuable investment that needs attention: our terra cotta pots.
Clay pots may look sturdy and strong, but they’re often fragile and easy to chip or break. Because they’re porous, they absorb moisture like a sponge. Changes in the temperature, or freezing rain and snow can cause them to crack as the clay expands and contracts.
Since good pots can be pricey—especially the big ones—you don’t want to leave them stacked beside the tool shed or standing in the garden, where the weather can damage or ruin them.
The best way to keep terra cotta containers safe is to store them before winter arrives. First, remove the plants growing in them and dump out the soil. (Some gardeners say their pots last longer if they leave the soil in, or if they leave their pots at least half-full before putting them away.)
Go ahead and clean any empty pots now by scrubbing them with a solution of one part bleach to ten parts water. Rinse thoroughly with clean water, and let them dry in the open air and sun for a few days, or until any remaining moisture evaporates. By cleaning them now, you'll have your containers ready to go next spring, and you'll avoid overwintering pests or diseases.
When the pots are completely dry, stack them upside down in a garage, shed or other area that stays dry and above freezing.
If you don’t have room for them indoors, move them underneath the eaves of your house or another structure. Avoid “nesting” the pots inside one another. Instead, stagger them as you stack, so each pot will get some air circulation. This will help keep them dry even if the humidity rises.
If your pots are too big to bring in, turn them upside down and cover them with a waterproof tarp. If they’re too heavy to flip, wrap them in the tarp and place them on their sides so rain and snow can’t accumulate at the bottom. It’s best if you can prop them or wrap them securely enough that they don’t rest directly on the wet ground.
For pots that will stay outside all winter because plants are still growing in them, try to move the pots onto a concrete surface, or use bricks, planter “feet,” rocks or pieces of wood to raise them off the ground. Otherwise, rain may cause the pots to stick to the earth in freezing weather. When you try to move them later, the clay can break or fall off in chunks or slabs.
Group your outdoor plants together for the winter in a sheltered spot (but remember you may need to water periodically if the rain can’t reach them because they’re underneath an eave or other structure). For extra protection, encircle the pots with a loose cage of chicken wire, making it high enough to cover the tallest plant. Stuff the cage with leaves or straw, working it in and around the plants, and use stakes or anchor the cage to the ground. Instead of chicken wire stuffed with leaves or straw, some gardeners wrap their outdoor pots with layers of bubble wrap for insulation.
And what about those containers marked as “frost-proof”? Unless they’re labeled for use in sub-freezing temperatures, they’re probably not freeze-proof. Most are best suited for mild winter climates.