Question
QUESTION: Hello Jacob and Jeff

  I hope your winter is going well for you.

  I was just reviewing the cephalotus section of your DVD and have a question about soil medium . You recommend one part peat, perlite and pumice. However, as in years past pumice is impossible to find in my area and while I can order online .. shipping costs are pretty prohibitive. So the question is, what can I use as a substitute for pumice ?

I have been growing my Mexican pings in 100% aquatic plant soil and they seem to love it. Your mention of cephs liking a slightly more mineral soil made me think this could be a good substitute. In addition it is coarse so that would allow for better drainage.  The other possibility would be vermiculite.

My cephs are growing indoor in a terrarium, RO water, currently in the medium they were bought in (and they need repotting) .. still living 90 north of NYC

As always .. thanks for your help  

Nicole

ANSWER: Hi Nicole,

The aquatic plant soil might work, but it needs to be inert in that it doesn't change the soil pH.  Mexican pings don't mind, and actually prefer an alkaline mix, but Cephs won't like that much.  Test it by taking a fair quantity of it and put it in some RO water and let it soak overnight.  After that test the water with cheap aquarium pH test kit. If the pH isn't above 7.0, you're fine.

You can also substitute the pumice with silica sand which should be pretty available in NY.  We buy big sacks of it at Home Depot.  It's often labeled as "Commercial Grade Sand".  That sand is good for lots of other cp mixes too, or any other place you need a high grade clean sand.

Good to hear from you.

Good Growing!

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

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

QUESTION: Hi Jeff

  So, I tested the aquatic plant soil as you suggested. The PH remained stable 5.4, but the TDS jumped from 18ppm to 136ppm.

Does the change in TDS mean I should head to home depot for the silica sand ?

Thanks again
Nicole

Answer
Hi Nicole,

That's interesting.  Try soaking and rinsing a couple times and see if you still get an elevated TDS.  If you do, then go for the sand.  If not, you probably just had some residual material from manufacturing that was on the media, and it will be fine to use.  As I recall, the aquatic plant soil is fired Kaolin clay.  That should be a pretty stable material.

Good Growing!

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