Question
Hey Jacob, Jason here. Just curious about something I saw in the Savage Garden.  Peter talks about perlite being somewhat alkaline.  So he said no more than 20% should be used with the peat moss. What is your opinion?  I have been using a little more than the 50 50 combination here for more water flow and cooling.  Anyway, just wondering you thoughts.

Answer
Hi Jason,

This really depends on where your perlite comes from, and how that manufacturer produces it.  Here in the Northwest, our perlite comes from Supreme Perlite in Portland, and most of our rock in this area is igneous.  They probably use pumice, granite, silica sand or other high silica rock as their base.  I've tested Supreme perlite a couple times (I've read the same thing you did in a couple other places too) and it is neutral.  However, I know you have a major manufacturer in Chandler, AZ that I've seen from some suppliers, and I don't know if their perlite is neutral or not.

What I would do is take some of your perlite and soak it for 24 hours in a container of distilled or RO water.  Test the pH of the water.  If it's above 7, then Peter's advice is probably good.  If it's 7 or below in pH, then it won't matter.

Good Growing!

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