Can You Use Softened Water on Plants?
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 gotten 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.
http://www.gardeningknowhow.com/plant-problems/environmental/softened-water-and-plants.htm
What are the potential problems of salt-softened water?
1) Soft water kills your plantsIf you use softened water on your house plants and your landscape, over time the salt will build up in the soil and cause your plants to die of thirst. If you live in an area that doesn’t get much rainfall, the salt will not get washed out or percolate deep enough into the soil to be diluted. High concentration of salt in soil decreases oxygen levels, causes the soil to swell and become compacted. When this happens, plants cannot get enough nutrients to their roots and they die.
Two ways to tell if your plants, trees, and grass have salt stress is if they have yellow tips on their leaves or have salt rings where the water sits as it soaks into the soil. Yellow tips will be less obvious on grass because you cut off the tips every time you mow.
2) Soft water poisons soilSalt is washed into your city’s wastewater through normal activities like showers, using the toilet and washing clothes. So even if you don’t use softened water on your own landscape, your softened water ends up in your city’s water source and is likely used to irrigate parks and agriculture. The longer an area is watered with salt-treated water, the more the soil in that area gets compacted and loses vital nutrients. Over time the high salt concentration will not only kill existing plants but also prevent new plants from growing in the poisoned soil.
3) Soft water harms the environment In cities where water softeners are allowed, the waste water must be treated for high salt content and there is an issue of where to discharge the salt when it comes out of the water. In places like California sometimes it’s discharged into the ocean which is expensive and can have long term effects on the aquatic environment. In other places, treated waste water is usually added to the local water source which may be a stream or lake and it will have the same detrimental effect on the fish and plants there.
4) Water softeners are water wasters! Salt-based water softeners have some convenient benefits, sure, but they are sneaky water wasters. Advocates say you’ll save money on detergents and appliance replacements, but you will use more water with a water softener than without. Why?
First of all, because compacted soil does not absorb enough water and will runoff faster than porous soil. You will need to water more often to get the same result. Also, you have to leach the salt out of your soil to avoid killing all of your plants – and that means regularly flooding soil with enough water to push all of the salt down deeper to dilute it or flush it to the surface and away. (Again, it has to go somewhere. Your lawn may be safe but you may be involuntarily poisoning the park down the street.) While this method is effective at washing away the salt, it also washes essential nutrients out of the soil which you will have to replace with soil amendments.
Softened water isn’t recommended for drinking so many people purchase a reverse osmosis unit which wastes at least a gallon of water for every gallon it produces.
http://valleycresttakeson.com/watermanagement/technology/the-hidden-risks-of-softened-water/
