gentian21@comcast.net gentian21@comcast.net
Tue, 02 Jul 2013 20:49:27 PDT
I avoid using fly screen for that reason.  There is a coarser 1/8" screen 
that works fine.  Many things can clog fly screen.
Frank Cooper

-----Original Message----- 
From: Rodger Whitlock
Sent: Tuesday, July 02, 2013 6:46 PM
To: Pacific Bulb Society
Subject: Re: [pbs] re pumice

On 2 Jul 2013, at 15:33, Ina Crossley wrote:

> I am using pumice in my mixes, but only recently.  I bought the 7mm one
> which seems to have a lot of dust and small stuff in it.  Does it still
> do it's job of drainage with all the small stuff filling any gaps.

If you intend to pot up a plant in nothing but pumice, be sure to wash it. I
have found that otherwise, the fines are washed down to the drainhole, pile 
against the piece of fly screening I customarily put over the hole, and 

Pumice by itself is a very good potting medium for certain plants. I use it 
Weldenia candida (which happens to grow natively near the tops of Central
American volcanoes, according to the literature), and a few honest-to-God 

Pumice is actually quite nutritious in a limited sense, containing a lot of

You are justified in your unhappiness with this supposedly-washed pumice 
been sold. Even when it's going into a potting mix, I wash it first over a 
shocking how much fine material comes out.

Rodger Whitlock
Victoria, British Columbia, Canada
Z. 7-8, cool Mediterranean climate
pbs mailing list

More information about the pbs mailing list