On Fri, 5 Jun 2009 08:47:56 +0100, prb wrote:

If you fill the hole with rubble or bricks etc, all you are doing is
making a nice sump for water to sit in thereby rotting the post. Fill
the hole with concrete.

Eh? Rubble with nice big gaps between it forms a sump and hole full of
concrete, with no gaps, doesn't?

Not that it makes much difference, as another poster has said the posts
will rot just above ground level. This is because the rot likes a
particular range of damp in which to live, to wet (in the ground) or to
dry (in the air) it doesn't live and the timber doesn't rot.

--
Cheers
Dave.