What's up everyone? Welcome back to another episode of the Epic Gardening

podcast. Today we're talking about purlite, what this stuff is and how do we

actually use it in our garden? What is it good for? So when you open up a bag of potting mix,

at least when I started gardening,

I saw a bunch of little white specks in it

and I thought, is that styrofoam?

What is that stuff?

But it's perlite, it's horticultural perlite. But the real question is, is purlite made out of?

So it's actually a form of amorphic volcanic glass,

although a lot of new gardeners like myself confuse it as something like styrofoam or some sort of light

additive. It's also called expanded pyrite and volcanic popcorn and I'll get into why when we talk about how perlite is made.

So if you looked at it under a microscope,

you would see that it is quite porous.

It's actually mostly air.

So those cavities that are in the purlite

help store nutrients and some moisture

that the plant might need, but they do drain off excess water.

So unlike vermiculite, they are not super water retentive,

whereas vermiculite is quite water retentive. So let's get into how it's made.

It actually begins as a naturally forming volcanic glass, which is a special

variety created when obsidian hits water. So this type of volcanic glass has a much higher

water content than other varieties and it sort of expands

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