Are Your Terra-Cotta Plant Pots Turning White? Here’s Why & What To Do

According to Kierslyn Kujawa, Earth’s Ally brand ambassador and plant influencer behind PlantedinPots, this white buildup is the result of a combination of the kind of planter you have and the water you’re using to water your plants.

“As the porous material that the planters are made of wicks away excess moisture from the plant,” she explains, “it leaves behind minerals that are in your water.” (If you’re using tap water to water your plants, there are likely trace amounts of salt and other minerals in it.)

This happens because certain porous materials, like terra-cotta, “breathe” out excess moisture, leaving the residue on the outside of the planter. If there’s enough moisture for an extended period, mold can even form (which will look fuzzy, as opposed to chalky).

But Kujawa assures mbg, “The white stuff on the outside of planters is typically no reason to panic.” And if the look doesn’t suit the aesthetic you’re going for, here’s what to do.