ISSUE 42  |  Italian Masters

Gardening 101: How to Prevent Cracks in Terra Cotta Planters

October 21, 2015 3:00 PM

BY Meredith Swinehart

Clay pots are as classic a garden feature as they come. (See our favorites in 10 Easy Pieces: Terra Cotta Planters). The best ones aren’t the little machine-made pots that run a dime a dozen. We like the big guns: giant, heavy, handmade terra cotta planters meant to last a lifetime.

But can they? Clay cracks. It expands and contracts as temperatures changes. As winter approaches, here’s everything you need to know about why terra cotta planters fall apart–and how to prevent yours from cracking.

Photography by Meredith Swinehart.

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Above: Potted lemon trees in the garden of the Villa Farnesina in the Trastevere district of Rome.

The Problem:

The main risk to terra cotta planters is that water trapped inside freezes–therefore expands–come wintertime and causes the pot to crack. Small cracks might go unnoticed during the winter, but try to move the pot come spring and it may fall apart.

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Above: Terra cotta window boxes in a small balcony garden on the island of Ischia, Italy. See more in Design Sleuth: Terra Cotta Window Boxes.

We sought advice from terra cotta purveyors Seibert & Rice, Wakefield, and Ritchfield Farms, and this is what we learned:

Strategy 1:

When the weather cools, empty any planters whose residents won’t survive the winter. Compost the plants and move the planters inside. We read some debate about whether or not to empty the pot of soil; some said leave it, some said remove half, some all. Store the planters upside down and away from the elements (in a garage or shed is fine). It’s critical to keep rain or snow from accumulating inside your planter; one freeze and it could cause a major crack.

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Above: Three terra cotta planters–one cracked–in a terrace garden in Bonassola, Italy. See the rest of the garden in Garden Visit: An Italian Terrace.

Strategy 2:

For those plants needing to stay outside all winter long, lift the pot off the ground. According to Seibert & Rice, water will freeze the planter to the ground during winter. If you try to move the pot later, it will crack or start to fall off in sheets.

At a minimum, elevate planters during winter using decorative terra cotta planter feet or bricks (but don’t block drainage holes). The easiest solution is to keep large terra cotta planters elevated year-round.

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Above: Photograph by Meredith Swinehart.

Strategy 3:

Drainage is critical. The more water stored in the soil of your planter, the more likely that a freeze will cause a crack. Be sure to leave ample drainage material at the bottom of the pot before filling with soil, and avoid covering drainage holes with whatever you use to elevate your planter.

Looking for ideas for those cheap terra cotta pots? Try DIY: Transform Terra Cotta Pots Into Instant AntiquesDesign Sleuth: Vertical Garden of Terra Cotta Pots, and on Remodelista, DIY: The Flowerpot Pendant Light.

N.B.: This post was originally published on October 1, 2014.

See terra cotta at home in Italy: