You would kill them with the salt content before you changed the pH much.

Just use the pellets of agricultural soil sulfur.

yeah, but i don't want to wait that long for it to work! i'm impatient

If you want to kill your plants faster than that, a flame thrower is effective.

are you referring to the salt content specifically, or another constituent(s)?

this water comes from a spring in a forest with green life sprouting around it as far as the eye can see, so while i am smart enough to not dump it in my garden without consulting experts (hoping there's one on here) and i guess i got a laugh, i'm more interested in the chemistry specifics.

the pure spring water does leave a white residue where it has dried, but it does not appear to be killing the plants or harming the stream it runs into... i understand common techniques of acidifying soil, but i don't have much knowledge of what the salt content of soil should be.

Are those water tests they offer free at Home Depot and Lowes specific enough to test for salts?

That white residue is carbonates ... alkaline mineral salts.

The plants growing around the spring are adapted to that pH. You mentioned lowering the pH for blueberries. Applying carbonates won't do it.

Aluminum sulfate will give it a quick drop, then the soil sulfur can sustain it for several years.

pH is commonly determined by meters that measure the electrical conductivity of soil solution. Don't mistake increases in measured electrical conductivity that are due to the presence of salts for those that are due to the presence of hydrogen.

thanks. i'm aware of the general process of acidifying soil, and some of the hazardous pitfalls, but this is a fair, clear explanation.

i'm also aware that i'm naturally impatient and have a house full of kids i'd rather be messing with than the garden soil, and thought i may have discovered a shortcut!

For future reference, 1) there are no units on those numbers, and 2) the pH of the water was not listed. If you had the pH it might have been easier to answer the question right off the bat. A little hard to tell from a list of salts whether it is acidic or alkaline, but the presence of carbonates suggests alkaline.

1) i know... i actually thought i'd added a comment about assuming they are ppm, but i see i must have left that out. but that's my assumption.

2) i don't have a liquid pH tester, so i don't know - i assumed the sulphretted hydrogen line would tip off someone with more chemistry knowledge than myself, but i tested it in my soil (which is typically about 7) and it dropped to about 5.5. best i can do.

but ultimately i do know how to lower the pH using standard methods, and i've since abandoned this as an option.

thanks everyone