Terra cotta pots heavily stained with calcium. Photo: www.olx.pl
Frustrated by the endless scraping needed to remove stubborn calcium (lime) deposits from flowerpots? There is a much simpler solution: a good soak in vinegar.
Calcium is alkaline, vinegar is acid: they’re essentially chemical opposites. So, if you soak a pot in vinegar, it will simply dissolve the calcium carbonate deposit.
The Method

Just soak your pots in a solution of one part white vinegar to 4 or 5 parts water and one teaspoon of dishwashing liquid for at least 1 hour before cleaning. Then remove the pot from the solution and rub it lightly with a damp cloth. The stain should come off with little effort while the soap will have loosened dirt particles, making their removal simple as well. If the pot is heavily coated in calcium, a 24-hour soaking may be required.
Finally, just rinse the pot with clear water and you’ll have a perfectly clean pot ready for reuse.
Note that anything acid will also do the job, including products like CLR cleaner (a popular calcium and rust remover), but vinegar is cheaper, likely to already be in your kitchen cupboard, environmentally friendly, and won’t irritate your skin.
Article originally published on November 12, 2015.
It is silly that so many new pots are painted with fake mineral deposits to make them look aged.
What a great tip. I hope I remember it come spring!