Tapla ??

Hey Al,

Do you have any suggestions for lowering the salt levels in water? Although I'm in the country I do not have well water, and I let my water sit for 24-48 hours before watering my indoor plants.. What can I do about the salt build up?

As I can see it best on the terra cotta pots, I will use that as my example. I can wash the pots just before watering..and then by the next day I can see the salt that has penetrated the pourous clay pot. I know that means there is plenty in some of the other pots that I can't see it as readily, and is trapped inside the pot/soil. When I water I flush but I dont think that is enough...

Thanks,
Tracey

Hi, Tracy. ;o)

There MAY be something aimed at gardeners on the market that claims to remove salt, but ......

The best bet is a reverse osmosis (RO) system. Ion exchange (IE) and electrodialysis (ED) are other methods that are possible. When we get to any possible products I mentioned in opening, it's good to know that chemical precipitation (adding a compound to knock the salts out of solution so they can be separated from the water) is only possible if the salt you are trying to remove has insoluble compounds as well. If you're trying to remove sodium or potassium salts, or nitrates, sulfates or chlorides, you'll have to use RO, IE, ED or evaporation; it's almost impossible (practically speaking) to chemically precipitate out any of these compounds.

Tapwater alone is unlikely to have dangerously high levels of dissolved solids (for plants). Your best bet is to be sure you're using a soil that allows you to water copiously, every time you water, and be sure your nutrient supplementation program includes low but frequent doses of fertilizer. That way, every time you water, you're flushing the soil, and the low doses of fertilizer keep the levels of EC and TDS (electrical conductivity and total dissolved solids - a measure of how much soluble material is in the water) at safe levels, even if these levels are high for tapwater.

I think it helps to have your irrigation water at room temperature, but allowing water to rest overnight isn't as likely as it used to be to help dissipate chlorine because of a change in technology that makes the chlorine compounds involatile - and in case you wondered about fluorine compounds: allowing water to rest isn't effective at reducing fluoride as is commonly thought; because, while pure fluorine is gaseous, it is never found in its pure state as a free gas. In water, it quickly combines with other elements or compounds and loses it's volatility.

FWIW - I have tons of terra-cotta pots I grow in (I prefer them) and they all get that crusty salt patina on the outside as they age. I think it looks cool ...... reminds me of my grandmother because hers always looked that way - but she always managed to produce healthy plants.

Happy New Year!!

Al

Thanks Al... Very helpful..

One more question... Does this mean it is safe to leave the salt patina on my terra cotta?

I love the terra cotta clay pots. and have been slowly moving most of my plants to them.. Seems to me they are easier.. since the color of the pot lets you know "something" of when they need a nice long drink. Being in the country, they fit into the ambiance as well. I have been tossing around the idea for about a year now, but I think I am going to paint my kitchen/dining room the "traditional" terra cotta color. With the right accents and my lovely plants.. I think it will look very nice..

I have some chocolate colored ones too..

Water tends to move from an area of low salt concentration to areas of high salt concentrations, so the (primarily) carbonates that accumulate on the outside of the container actually draw water with a low salt concentration toward the crust on the outside. When the water passing through the walls of the container evaporates, it leaves behind the dissolved solids to add to the crust (patina sounds soo much better) ;o) So yes, it's safe and won't hurt your plants.

Al

Thanks.. I knew I could count on you.. : )