David Hare-Scott wrote:
tibbar wrote:
'songbird[_2_ Wrote:
;954136']tibbar wrote:
....-
My question is can I use limestone chippings for the ballas it
appears to be the cheapest aggregate unless you members know better,
I'd appreciate any information.-

chipped limestone will have very high pH.

Thanks Songbird for your reply, does having a high pH make them
unsatistactory for growing tomatoes?

freshly chipped limestone will be quite different
from aged limestone. in between there will be
rinsed limestone.

i wouldn't consider any of them optimal. for
a few dollars more there are better substrates
that you won't have to fight continually to keep
the pH in range. so sure it might cost less to
start, but then you pay later.

the hydroponics poster here often is Gunner.
i'm a dirt gardener with much experience with
crushed limestone because we have around a hundred
tons of it here and i've studied it in various
circumstances as a result over the past 15 years.


High pH in soil will reduce the absorbtion of some minerals which become
less soluble. Most veges (this is a generalisation) like it about 6-6.5
that is slightly acid and IIRC tomatoes are in that group. The question
that I cannot answer with certainty is will limestone chips in the aggregate
layer have the effect of raising pH too high. I am guessing there will not
be very much effect in the time that tomatoes grow as limestone chips will
not dissolve readily.

note David that the OP is starting from scratch.
with new chipped limestone which is a harsh substance.
even with a lot of rinsing it takes quite a while to
mellow.


I take it that there is water in the aggregate layer. If so test its pH and
you will know and nobody needs to guess. A dye indicator pH test kit is
cheap and accurate enough for the purpose and will always be useful if you
are going to grow veges.

*nods* i'd certainly use something else if it
is available.


songbird