Cleaning hard water deposits?

[Dan W.]

Does anyone have any miracle solutions to cleaning pots? We have a lot of hard water around where I live and it can be a big problem with pots. If anyone has experience and good advice to share I would greatly appreciate it.

Thanks!

Dan

 

[edprocoat]

I think the safest way on a pot would be to use white vinegar and a small brush, one of the hobby brushes that look like a toothbrush with the black stiff plastic bristles. I know that the product CLR, Calcium, Lime and Rust remover works instantly, but its an acid based product that I would think could leave harmful poisons in the absorbent pottery that would hurt or maybe kill your plant. White vinegar is an old remedy for lime scale, (hard water deposits) that really works well but takes a little effort.

ed

 

[Dan W.]

Thanks ed

 

[crust]

ABS I think actually did a comparison article on this issue some time ago. Don't remember which issue. The low down was nothing is a miracle solution to get it off other than don't use mineralized water. They tested the usual stuff i.e. Limeaway, CDR, Muratic--using a abrasive scrubby helps some.

Nurseries around my parts have enough mineral and PH problems where they not only soften (with a potasium based component water softener) the water but also acid inject it to adjust PH and reduce mineral percipitation on plants and pots of their stock. I try to use rain water but when I run out I use the well water and defeat my long term efforts seemingly in a short while. That is why I added another 291 gallons of water storage capacity this past week.

 

[JudyB]

I've tried the vinegar thing, I have a couple pots that have it bad... It never really gets rid of all of it. I read somewhere to soak the pot in cola. I'm going to try that at some point!

 

[Eric Schrader]

Vinegar is a weak acid so it will take a long time to dissolve the Calcium deposits. Try soaking the pots in straight (5%) vinegar if you want to use it. Alternately, buy some muriatic acid (pool supply) which would remove the Ca deposits probably instantly. High fired clay pots are not porous, clay vitrifies at high temperature - that's why high-fired clay pots can withstand freezing temps - because there is not water in the non-existent pores to expand and crack the pot. If you're concerned about the acid hanging around then use baking soda (Calcium Carbonate) to neutralize it.

All that said - I would do something much more simple - coat the pot in walnut oil (from mashing walnuts in an cloth sock, not from a commercial can of oil). This doesn't remove the deposits but it does make them hardly noticeable. The oil will wear off after a while but even if you clean the pots with acid the deposits will return anyway.

Or switch to using RO water, that will eliminate the problem and make your plants grow better all at the same time. Basic RO systems start around $150 - look for one at a hydroponics supply - they're designed for high volume while not filtering quite as much of the dissolved salts as the drinking water type and they waste less water to make the RO water.

 

[JudyB]

Eric, thanks for those solutions. I've switched to rainwater all the time now, so I've solved my issue. Too late for a couple of pots however...

I'll try the walnut oil. I have plenty of black walnuts around here... (for now till the canker gets em. )

 

[Dan W.]

Thanks for the advice everyone. I'm using mostly rain water as well but I'm still getting the build up when I don't. I may have to add to my rain water storage.

 

[jk_lewis]

I use a Dremel with a bristle brush. It works fine and does not mark up the pots. Works on glazed and unglazed pots. They do NOT work with rough-finished pots.

 

[Ang3lfir3]

I use CLR or Vinegar (Rice Wine Vinegar, its what we have in the house ne ways) on pots that I purchase that have the issue.... we don't have mineral problems in our own watering so that part works out.. just have to clean the pots before I put em to use... I never get all the minerals off but that works out fine for me... makes the pots look older

 

[crust]

Vinegar is a weak acid so it will take a long time to dissolve the Calcium deposits. Try soaking the pots in straight (5%) vinegar if you want to use it. Alternately, buy some muriatic acid (pool supply) which would remove the Ca deposits probably instantly. High fired clay pots are not porous, clay vitrifies at high temperature - that's why high-fired clay pots can withstand freezing temps - because there is not water in the non-existent pores to expand and crack the pot. If you're concerned about the acid hanging around then use baking soda (Calcium Carbonate) to neutralize it.

All that said - I would do something much more simple - coat the pot in walnut oil (from mashing walnuts in an cloth sock, not from a commercial can of oil). This doesn't remove the deposits but it does make them hardly noticeable. The oil will wear off after a while but even if you clean the pots with acid the deposits will return anyway.

Or switch to using RO water, that will eliminate the problem and make your plants grow better all at the same time. Basic RO systems start around $150 - look for one at a hydroponics supply - they're designed for high volume while not filtering quite as much of the dissolved salts as the drinking water type and they waste less water to make the RO water.

Any specific recomendations on systems, sources and brands??

 

[Attila Soos]

Walnut is pretty decent, but yesterday, at the BonsaiThon at the Huntington, Larry Ragle did a demo for me, using another nut. He cleaned up all the white spots on a small pot in 30 seconds. The pot looked amazing, after the demo. He told me that this is his own invention, so nobody really knows about it, except a few of his friends.
I am torn, whether or not I should share it here with the whole world, since it is not my idea. But maybe you guys can figure it out, it's a large nut and tastes very good. You can always find a few in those fancy mixed nuts cans.

 

[rockm]

Far and away, the best non-destructive method to remove these stains I've found is to bury the pot in the ground for a season or two, or mulch it under pine bark for the winter. I've never had problems with lime scale since I began mulching my pots and trees under pine bark for winter. The acidic environment tends to break down build ups from the previous summer.

Ground burying can also remove the stains over time through microbial action too.

Of course, you can't use the pot while this is going on though.

 

[Attila Soos]

Sounds interesting, but makes sense.

 

[Ron Dennis]

Far and away, the best non-destructive method to remove these stains I've found is to bury the pot in the ground for a season or two, or mulch it under pine bark for the winter. I've never had problems with lime scale since I began mulching my pots and trees under pine bark for winter. The acidic environment tends to break down build ups from the previous summer.

Ground burying can also remove the stains over time through microbial action too.

Of course, you can't use the pot while this is going on though.

When we had an unexpected cold spell, I mulched all of my trees for winter protection in pine mulch due to time restraints and tryiny to protect the trees in the dark with only a flashlight. Since we have had such a warm winter and several trees are really leafing out, I pulled them out of the mulch over the weekend. I noticed an improvement in some pots in this brief period of time.

 

[jk_lewis]

bury the pot in the ground f

There's absolutely no doubt that this works, but some of us don't have that many pots to spare for a season, and since most of my pots are about 3" in diameter, I'm always worried about losing one.