Hi johnmcd348,

Very interesting question. A good cost/benefit comparison. Here is the financial question to your thread. Your conditioned water is the more costly water in your home. What is the cost per 1,000 gallons of water for your system versus non-conditioned water. If you use the more expensive water to irrigate the garden, is it worthwhile to make a connection to the non-conditioned water line and get it to your garden? The nutrients that would be in your untreated water are in negligible concentrations (part per millions or billions) and are not a factor to consider when thinking of fertilizer amounts to use in your garden. The more water you use the cheaper your cost of water then use the conditioned water. If it is more costly the more water you use because of maintenance costs then use the unconditioned water. This is just mho without really having all the facts. Questions that beg to be asked. How big a garden do you have? Is there another connection point from your mainline near the garden? What is the cost of your osmosis system? Is there a routine maintenance cost for the system? How much water do you use a day/week/month? Someone with more knowlwdge about this pipe up. Have fun with water. Aloha.

johnmcd1048, I am struggling with the answer to this question myself. At this time I would have to say that it might be bad to use softened water for the landscape.
Check out 'Water for Irrigation'. at this site.
ag.arizona.edu/turf/tips201%20.htm - 7k