[brownrexx]

I use softened water for my seedlings without a problem.

Water softeners add a minimal amount of salt to drinking water and the main reason that people do not use it for outdoor watering is to save wear and tear on the water softener as well as money on salt. It is not because the salt will hurt the plants. All of our outdoor faucets are fed with unsoftened water.

The amount of salt in your water is determined on how hard your water is and that determines how much salt is used to remove the hardness ions from the resin bed but even with really hard water the amount of residual salt in the drinking water is minimal. The softener only uses the salt that it needs and the amount of salt in the tank is immaterial.