Expert: Sarracenia Northwest - 4/7/2010

Question
I have a reverse osmosis filter for our drinking water, but the water is first treated by a water conditioner ( soft water ) Seems to me I read that was not good, but I can't remember why? Will that kill the plants if I use it? Buying distilled get very expensive. Also I put out 3 garbage cans to collect rain water. Will that be OK to just leave those out and use that until it's gone? What if I leave it out all winter and collect a lot; will the water be OK sitting there all summer if I collect enough? I believe my plants are the whilte and red top pitcher plants.

Answer
Hi Martin,

Your correct in what you've heard that softened water is bad for carnivores.  It's fairly bad for houseplants too.  The reason is that softeners replace hard water minerals such as calcium and iron with sodium (salt).  That quickly becomes toxic if it builds up in soil.  However, if you take that water and pass it through your reverse osmosis filter, it will take the salt out.  Having the water softened before it goes through the R.O. unit actually extends the life of the membranes.  Salt is easy for R.O. units to remove, iron isn't.

Your collected rainwater will be fine.  Just don't drink it. :)  The plants don't care about bacteria.  If your containers are open be sure to treat for mosquitoes with dunks so you don't end up breeding them.  The dunks are safe for plants.

Good Growing!

Jeff Dallas
Sarracenia Northwest
http://www.cobraplant.com