
Are your clay pots are stained with a white deposit? Such stains build up over time due to the calcium (lime) present in hard tap water and to surplus minerals found in the fertilizers we use to water our plants. Both tend to migrate to the outside of the pot wall, since terracotta (clay) is permeable, then accumulate there, resulting a white powdery deposit officially known as efflorescence.
Not so long ago, the most frequently asked question about efflorescence on clay pots was “how do I remove it? (And indeed, it is hard to remove.) But that’s not so much the case today, because this accumulation is no longer regarded as being dirty, but has become a desirable effect. In fact, you may hear it mentioned as “patina” and it gives the pot that coveted aged look that in fact increases its value. And it’s not just anyone who says so, but the American queen of good taste, Martha Stewart.
Inflorescence is not harmful to plants, at least not when it is on the outside of the pot. (Inside the pot, excess calcium and fertilizer accumulations can however “burn” the roots that touch it, resulting in a bit of root pruning.) Rather, it is said to “give the pot character”. So, it’s a good thing.
Artificially Aged Pots

Given the current attitude that stained terracotta pots are desirable, it should come as no surprise to anyone that garden centers now carry “pre-stained” pots, terra cotta pots that were soaked beforehand in a lime solution in order to accentuate their efflorescence… and that they are much more expensive than “clean” pots! Even plastic and fiberglass pots designed to imitate terracotta in color and texture are now sold painted with different products that mimic the desired calcium deposit… I mean, patina.
Not only that, but on various Web sites, including Martha Stewart’s, you’ll find recipes on how to make your brand-new terracotta pots look positively ancient. I kid you not!
Less Work for Gardeners
As a laidback gardener, I can only applaud this attitude. After all, eliminating calcium stains from clay pots is an arduous task, involving soaking the pot in water and vinegar to loosen the deposit then scrubbing hard with a metal brush to remove it. (See Clean Your Pots with Vinegar for more information.) Instead, just proudly put your dirtiest pots out in full view, knowing that this is the epitome of good taste!
(I can’t wait until dirty gardening clothes become just as trendy! I have so many pants with dirt stains on the knees that simply will not come out!)
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