On Apr 15, 10:44 am, Jangchub wrote:
On Mon, 14 Apr 2008 22:33:28 -0700 (PDT), Frank
wrote:

50 / 50 vermiculite / perlite mix, no soil, no peat, no compost.
Excellent water handling characteristics, pH would remain dead
stable. No pests, no disease. Feed with organic tea to replace
the missing OM portion. Would this work as well as a good
standard potting mix such as Pro Mix?

The problem with this mixture is that there is too much air space and
plants will not develop roots the way they ought to. Generally, that
air space is filled with peat or coir and the moisture in that portion
of the mix is what supplies feeder roots or root hairs with capillary
water.

Coarse sand? Shredded newspaper?

Why do you want to use this mixture?

Trying to do without peat for various reasons. Paghat
has a good article on her page that explains why. pH
maintenance is an escalating battle once the stuff starts
breaking down, which kills off everything for mysterious
reasons. Coir would be a great substitute, but it's too
hard to find in the Baltimore area.

Meanwhile, the tea I've been brewing works beautifully.
I'm wondering if I can't use it in full place of the solid
OM portion, eliminating a source of many headaches.