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.
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.
With seed-sowing season just getting started and about to accelerate (March and April are the big months), it’s worthwhile for gardeners to look into their stock of flower pots. If you’re like me, you have a huge supply of pots, six packs and plant trays recovered from gardening sessions of previous years. These pots can almost always serve at least one more time and usually almost indefinitely. (Six packs are the most fragile.) It’s a question of economics on one side and respect for the environment on the other. Yes, most of the pots are made of plastic that can be recycled by specialists, but it’s even more environmentally friendly to reuse them, saving recycling as a last recourse.
However, pots must be thoroughly cleaned before reuse in order to eliminate any microbes or insect eggs that may be present in the residues that cling to their sides. After all, seedlings and cuttings require as sterile an initial environment as possible.
The most obvious way to clean pots is simply to wash them by hand with soap and fairly hot water. If mineral salts, seen as a white or yellowish deposit on the side some of the pots, have formed, try soaking them in a solution of water and vinegar 24 hours before washing them. Vinegar being acid, it will soften the mineral deposit, which is alkaline, making it easier to remove.
But washing pots one by one takes time. Surely there must be a way to wash them quickly and with less effort? That’s the question I first asked myself about 30 years ago.
At the time, my wife brought up the idea of buying a dishwasher. With two parents working full-time and three children at home, it would save a lot of time. I objected however. Since indeed we had three children, I felt that we had enough cheap labor to handle the task. So why spend hard earned cash on a dishwasher? So I vetoed the expenditure and for some time we didn’t talk about the idea.
But I started thinking. Couldn’t a dishwasher also be used to clean pots? I had accumulated at that time an impressive pile of dirty pots and was hesitant about washing all of them by hand. The more than I thought about it, the more it seemed logical. So one day, to the surprise of my wife, I announced that she was indeed right and that we needed a dishwasher. So we bought one and had it installed.
I suspected that my wife would object to the idea of my putting pots with dirt and who knows what else in a machine designed to wash tableware, so I waited for her absence before filling the dishwasher with pots. I added the usual detergent and started the machine. Everything seemed fine at first. It was only towards the end of the cycle that I noticed an odor of burning plastic wafting through the kitchen. Opening the dishwasher, I discovered to my horror that the smaller plastic pots had been tossed all over by the force of the water and that some had fallen onto the element where they were slowly melting. Fortunately I was able to clean everything up and ventilate the apartment before my wife got back.
What a disappointment, though! All that money wasted on a machine that did not even fulfill its promise! And I still had that huge pile of dirty pots to wash. What to do?
I started to think. Perhaps the washing machine (clothes washer) might be able do the job? And we already had one, so there was no added expense involved! So, again when my wife was absent, I filled it with a load of smaller pots, the ones that didn’t stay in place in the dishwasher. I added detergent and set the cycle to “Delicates”. Eureka! The pots came out in perfect condition and absolutely spotless! Of course, I emptied the washing machine and carefully cleaned the filter, which was actually fairly clean except for a bit of perlite, before my wife got back.
She eventually discovered the subterfuge a few years later when a friend spilled the beans… but even came to accept it as yet another of those weird things her husband does. I am now allowed to use either machine for pot cleaning, as long as I clean up afterwards. The dishwasher is ideal for terra-cotta pots, medium-sized plastic pots and plant trays while the washing machine (do use the Delicates cycle!) is perfect for smaller plastic pots and six-packs. But I still wait until my wife is out of the house before starting a load. It’s a question of tradition.
Oh, and I should warn you: do not try to wash terra-cotta pots in the washing machine. My wife doesn’t know about that one and, really, she doesn’t need to know. I’m counting on your silence!