Question

Drosera pathetica   QUESTION: I am having a terrible time with the Drosera family. Currently I own Capensis, Prolifera and Binata and all are doing terrible. My Dionaea, Sarracenia, and Nepenthes are all doing amazing. All of the plants are in long fiber sphagnum moss with water trays, and under two 40W florescent lights for 12 hours a day. The heat stays between 70F-90F and the humidity stays between 55-85%. The Drosera are constantly getting short, wide, malformed, weak, and dewless leaves. I have tried raising them 6-8 inches under the lights with no change, raising them 2-4 inches under the lights with no change and lowering them 8-12 inches under the lights with no change in leaf structure.

I am all out of ideas. Please help.

Thank you,
Tom

ANSWER: Hello Tom,

Some other things to look for would be minerals in your water supply and chemicals that might affect Drosera, but not your other plants. Sarracenias and Nepenthes tend to handle slightly harder water than most other carnivorous plants, so if your water supply has some mineral content, it could build up slowly in your Drosera soil and eventually harm them. Carnivorous plants do tend to produce malformed leaves when they encounter too little light or a buildup in minerals or chemicals that harms them in some way. How long has it been since repotting? Maybe they need a soil change in case anything has gotten in the soil over time.

As you indicated, this is one of those involved questions where the answer could be a number of things. I advise you to send this question to Sarracenia Northwest as well to see if they know of anything else that I can't think of that might be causing your Drosera problems.

Christopher

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

QUESTION: Thank you. I am currently using "zero water" to filter my water.

http://www.zerowater.com/

I change the filters when they get to around 100 PPM.

I just checked the water trays and they are at 100 PPM do you think the soil is contaminated and should be replaced?

ANSWER: Hello Tom,

We may have found the culprit then. Most carnivorous plants cannot handle hardness of over 50 ppm of mineral solids in water... like potassium salts, magnesium and such; the minerals that make water taste good to us humans is harmful to them.

The water purifier you have looks good if it actually does remove all mineral solids from the water via ionization. If it used salt to soften the water it would also be unsafe to use on your carnivorous plants.

In any case, change the soil and make sure the water hardness reading remains far below 50 ppm to keep your plants safe.

Christopher

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

QUESTION: Thank you, on Friday 4-10-09 when I last checked the water it was at 10 PPM that is the only thing about this filter I hate, it is not a gradual increase. Either the water is good or bad, no in between. Do you still feel the soil is contaminated even though it has only had hard water for about two weeks or less?

Answer
Hello Tom,

Considering the leaf deformities, it would be better to be safe than sorry when dealing with contamination in carnivorous plant soil. Once minerals build up and the Ph begins to sour, you can try washing purified water through it a few times to flush out the impurities, but to be certain they are gone, replace the soil completely.

Christopher