I believe that salt-based water softeners don't release salt (as in, sodium chloride) in the water, but just a little sodium. So you're replacing a whole lot of calcium, magnesium, and iron with a little bit of sodium. Sodium isn't a plant nutrient, and it takes a lot to harm plants. Calcium, magnesium and iron are nutrients, but a lot can harm plants. The process can reduce pH, so you might make sure you know what's up with that. With that caveat, I don't see an issue.

Does the water softener function on the outdoor tap? It is very rare that an indoor softener works on the outdoor spigot. One typically requires a dedicated outdoor softener for that application as they must be able to withstand conditions your indoor faucets never encounter :-) If that is the case, then I doubt you have much to worry about.......I doubt the aerogarden consumes that much H2O!

You actually have to trace the softeners. Some do connect to the entire system. Some do not. Sometimes this seems random, so I'm guessing (I have no clue) that it depends on local codes and if and when such codes are updated, if ever.

Sometimes they have to shut it off. Sometimes the installer bypassed the outside water system.

As to how much sodium is in the water, only the amount of salt consumed by the system proportionate to the water would be able to tell us that, which would be calculable using your salt usage and your water bill, at least roughly. Amounts used aren't vast...but it can take thousands of gallons to water the lawn, for instance, and an inch of water per square foot is 0.7 gallons. It adds up.

Many a time I've had to have a user look because the sodium levels in their soil were odd on their soil test. Sodium soil-binds, and how harmful it is depends on how easily it gets flushed out. In areas with heavy rains, it's not so much of an issue most of the time.

Keywords "Most Of The Time." Droughty periods can override that if watering the lawn and gardens a lot, and of course, plants that receive nothing but tap water would have their own concerns.

I certainly have seen it impact soil tests, particularly with very hard water (I have no idea as to how hard your individual water is, whether you're on well water or city water, and so on), in more arid regions (Cleveland not being one of those, fortunately, but more arid than most maritime areas), and in areas influenced by other sodium sources (sodium levels naturally being high in the soil from the get-go, being roadside and influenced by salting in the winter, salt in natural rainfall [planetary and not of general concern], or salt spray [not an issue in Cleveland]).

If concerned, certainly get a reliable soil test that includes sodium levels. While sodium is toxic to plants at high levels, even lower levels of sodium are detrimental, and it's easy enough to flush out of the soil if it turns out to be a problem. Plus a good soil test (I use and recommend Logan Labs, personally), can tell you a vast amount about your soil and suggest many other corrections to help out your plants!

It's probably just fine, unless your softener is acting up, or you accidentally add too much salt. I managed to kill all my tomato seedlings by watering them with softened water, so I never use it for seedlings now.

Linda

I have well water and I do not know how hard it is. I have had issues starting seedlings from time to time and this might be the cause!

All water for everything goes through softner first but there is a bypass I have to manually turn on and off.

Then, just for "safety's" sake (so to speak) and to save a little on softener salts, I'd turn it off before watering the outside. There's no sense in ever increasing your soil's sodium ions for any reason if there's no need.

The natural ions from your well water will probably be calcium, magnesium, and potassium for the most part. It's not really what you want in your wash-water, but the plants won't mind--and it's all things that have leached out of the soil anyway. Somewhere. :-)

Certainly do so before starting seedlings--and remember to run the water in that case enough to clean out the softened water in the line. Seedlings, in particular, are almost always more sensitive to salt damage than the adult of any species.

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ETA--We'd have to go into a discussion of relative salt damage here. Suffice to say that sodium is generally far worse than calcium or magnesium in the water. For sensitive plants, try using a gallon of the cheapest distilled water for the initial germination and growth phases if you have trouble--that'll save you a whole lot of headaches for trays of really pricey and sensitive plants. For grass seed and most other things, well water will be just fine.

Seems like if you can turn it off, it's a waste of money to water the garden with salt treated water when that's not a plus for the garden. It's death over the long haul to indoor potted plants, I know that. We installed a rain barrel water storage system for just this reason, watering the garden. Saving our well pump and bypassing any softener issues. Great for starting seedlings too, no need to buy distilled water. Our other option used to be using water from the creek through the irrigation system. Lot of schlepping from the pump area to the specific garden spots, and that water was a tad funky too.