When deciding what type of container is best for growing your plants, you’ve probably at least considered traditional unglazed terracotta pots. They’ve long been a staple of home gardening, and for good reason: they’re relatively inexpensive, can be reused, and are porous, allowing air and water exchange.
But they also tend to develop white spots on the outside of the pot. And while some people consider it part of their rustic charm, others find the film unsightly and you want to get rid of it. Anyway, here are some ways to remove white residue from inside and exterior terracotta pots.
What is the white residue on the outside of terracotta pots?
the white film or crust that forms outside (or inside) clay terracotta pots is soluble salts. Hard water (which includes most tap water) contains salts and minerals. OWhen you use it to water your plants and it eventually evaporates, it leaves those salts and minerals behind as white residue, much like what happens on shower heads.
Meanwhile, if you have softened tap water, you may still see this white stuff on the outside of your terracotta pots. But in this case, it is probably caused by the fertilizer in your soil, which contains minerals. Because these clay pots are porous, the soil minerals seep through the jar and may appear as residue.
How to clean white residue from terracotta pots
If you really want to thoroughly clean the jar, it’s best to do it when the jar is empty. Otherwise, depending on the condition of the plant, you may want to consider removing it from the pot for the cleaning process, especially since there are likely some soluble salts inside as well.
Here are three common methods:
Make a solution of one part vinegar to 20 parts water. Soak the jars in the solution for about 30 minutes, then scrub white spots and residue. Rinse thoroughly with clear water, then let the pot dry.
Make a solution of one part bleach to nine parts water, and use it to scrub the inside and outside of the pot. Rinse thoroughly with clear water, then let the pot dry.
Make a baking soda and water paste and use it as a spot treatment to remove white residue.
Is it okay to leave the white residue on the jar?
Although it is always a good idea to remove the white film that forms on the inside of a terracotta pot (to prevent soluble salts from entering the soil)leaving the residue on the outside pot is usually fine. According to an article in Horticulture Magazine, “salts outside the pot will not harm the plant.”