On 10/26/2012 11:23 AM, David Hill wrote:
On 25/10/2012 22:36, Bob Hobden wrote:
"David Hill" wrote ...

I am wondering what effect a liberal dose of ground limestone as well
as a load of limestone gravel would have on an acid soil, with an eye
to making it more suitable for grapes.

The roots of Grape vines go deep, very deep, so what is under your
topsoil?


Clay overlying rock, we are on the side of a mountain, but I'm not
certain of the type of rock, but we are on old pasture that never saw lime.

We were always told to add gypsum, and have done so in the veg patch
(when we were doing veg) to both make the soil less heavy and raise the pH.

Grape vines do indeed go very deep, and wine makers tell me they like to
be stressed a little for the best fruit. In many areas of France there
is little to no top soil. Some vineyards have taken to displaying core
samples, big clear plastic cylinders filled with different layers of
soil, schist, etc. It's fascinating to see how the vines do well under
sometimes really difficult conditions.

This is a US site but it does have some interesting notes on soil
structure (and pH), perhaps it might be worth a look:
http://arcserver2.iagt.org/vll/learnmore.aspx. (In it they say the top
soil is the most important factor though, which is contrary to what I've
been told many times...)

-E