Most of the time it is not a good idea to water your garden with softened water. The reason for this is that softened water typically has a high amount of sodium, which is attained from salt. Most plants cannot tolerate high amounts of salt. The sodium in softened water actually interferes with the water balance in the plants and can kill plants by “fooling” them into thinking they have taken up more water than they have. Softened water essentially causes the plants in your garden to die of thirst. Not only does the salt in softened water hurt the plants you water with it, the salt in the water will build up in your soil and will make it difficult for future plants to grow.