Question
QUESTION: Hi I am a somewhat experienced grower I maintain... Umm I am not sure like 50 species or so,My mom thinks I am overworried and narotic about water purity. Our well water has lots of minerals I tested by simply evaporatiing a half gallon of water seeing white mineral depsots after it all evaporated. In your own words how pure/clean does the water be for general CPs taking in consideration some genrea like nepenthes and other may tolerate more minerals than other generea.
hanks I rgeatly apreciate the help,
Josh

ANSWER: Hi Josh,

It all comes down to understanding what kind of impurities are a problem for carnivorous plants and which ones are not.  For instance, you could have water full of lead, cadmium, and mercury and it probably wouldn't have much effect on cp.  It would kill us over time, however.  If the water has lots of calcium and magnesium, common hard water minerals, it is just fine for us.  It'll make your bones stronger.  Unfortunately, it will kill Venus flytraps, sundews, and other carnivorous plants over time.  Usually the hardness will be measured in total dissolved solids (tds), and expressed in parts per million (ppm).  Generally speaking, if your water is 50ppm or less it is safe on cp for a period of time.  As an example, when we lived in Portland, OR our tapwater had a tds of 20ppm.  We used it on our plants for years with no problem.  When we moved the nursery out to the country we were on a well and our water was about 130ppm.  We used the well water for the first year untreated and killed most of our Venus flytraps.  Now we use a reverse osmosis unit which brings down the minerals to 7-10ppm.

So, what's the bottom line for you?  The good new is that Nepenthes are among the least sensitive to harder water.  Sarracenia will also tolerate hard water for quite some time before showing problems.  Venus flytraps and sundews are the most sensitive to hard water.  Get your water tested to see how hard it is.  Aquarium stores can often do this.  If you are in doubt about your well water, try an use rainwater or distilled water as much as possible for the sensitive species.  Use the well water for Nepenthes and Sarracenia.  The Nepenthes are quite tolerant, and the Sarracenia get the minerals flushed our by rain since they grow outside.  (You are growing them outside aren't you? :))


Good Growing!

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

---------- FOLLOW-UP ----------

QUESTION: I have them currently in an unheated shed,
plus 4 younger siblings so things can just be inside or far far way from them. I recently used a activated carbon filter since it has been lowering down the white deposits a good amount. I live in coos county, other than siblings I'd leave them outside. I have flushed the sarracenia and dionea with RO water. I have some snow melted water that I will use to flush out many of my drosera but I need to somehow get back to RO water. I am sorta wondering does live sphagnum water actually remove minerals from water or is that a myth  like if I dressed everything I ahve with it would it in theory use it for growth?
Thanks for the help !
I have a drosera setup so I guess they need it the most.

Answer
Hi Josh,

Thanks for letting me know you live in Coos County.  Since you get more rain down there than we do here in Estacada, just collect rainwater for your plants.  The melted snow is fine too.  There's nothing magical about R.O. water.  Rainwater is just as good if not better.  During the summer you may need to bring in water during dry spells.

Carbon filters such as Brita and Pur are good at removing chlorine and heavy metals, but don't remove all that much in minerals.  It's better than straight hard well water, but most of the calcium is still there.  If you would like, I can test your water if you send me a sample.  Go to the website, http://cobraplant.com/index.php , and go to the "contact us" link at the bottom of the page.  There you'll find our mailing address.  Try to send me at least two ounces.  Include an e-mail address and I'll e-mail you the results.

Live sphagnum moss as a top dressing is good for the plants and looks nice, but it won't remove minerals.  In fact, if your water is really hard, it will kill the sphagnum.


Good Growing!

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