On Wed, 15 Jun 2005 21:16:14 +0100, Martin Brown
wrote:


He has answered your question in a strict sense. Adding vinegar will
lower the pH, but since calcium acetate is soluble and calcium carbonate
is not you will gradually clog up all the pores in your compost. The
plant roots will eventually suffocate - only a matter of time.


I find this a truly bizarre suggestion. The pore volume in a good
loamy soil is probably around 50% of the total volume. That represents
a huge amount of calcium that you'd have to deposit to block them,
compared with the amount of calcium available in the water. Even if
you argue that the micropores become clogged first, in anything other
than a bone dry soil these pores contain water (due to surface tension
and capillarity), not air. Air occupies the macropores, as do a lot of
the plant roots. So the roots won't suffocate.

And why should calcium acetate clog pores anyway? It's in solution, as
you rightly say, and apart from a small amount of base exchange with
the clay minerals and organic acids present in the soil, the bulk of
it will remain in solution, just like potassium or even the complexed
calcium you suggest is present when ericaceous fertilisers are used.

By what mechanism is this clogging supposed to occur? Where did you
get such an idea from?


--
Chris

E-mail: christopher[dot]hogg[at]virgin[dot]net