On Jun 7, 10:34*am, Andy Dingley wrote:
On 7 June, 09:31, NT wrote:

Unused plaster will bind the soil, used lumps wont.

Run it through a cement mixer and a couple of rocks as a ball mill. So
long as you crunch it down enough to go through a sieve, it's fine.
Even just soaking it in an excess of water would be enough (this is
plaster, not cement).

I wouldn't add "rottable garbage" to soil either, it's much better to
rot this down separately. Otherwise you'll be short of nitrogen and
lawns in particular would suffer badly.

So they say, but I've not seen this happen in practice. If you added
wood shavings or plenty of paper I daresay it would.


NT

On Jun 7, 8:57*am, Chris J Dixon wrote:
Having just extended a flower bed to incorporate what has been
lawn for 40 years, I am left with some pretty solid clay soil.

Gypsum is recommended as a soil improver, but appears to be sold
in garden centres as a proprietary product costing nearly 5 for
2.5 kg.

http://www.capitalgardens.co.uk/clay...itioner-p-6321....

On the other hand, I can pick up a 25 kg bag of multi-finish
plaster for under 5, and AFAIK this is essentially the same
material.

Any reasons not to go with plaster?

Chris


Building plaster has other stuff in it besides gypsum, anyone know
what those additives are?


NT

On Mon, 07 Jun 2010 08:57:04 +0100, Chris J Dixon
wrote:

Having just extended a flower bed to incorporate what has been
lawn for 40 years, I am left with some pretty solid clay soil.

Gypsum is recommended as a soil improver, but appears to be sold
in garden centres as a proprietary product costing nearly £5 for
2.5 kg.

http://www.capitalgardens.co.uk/clay...er-p-6321.html

On the other hand, I can pick up a 25 kg bag of multi-finish
plaster for under £5, and AFAIK this is essentially the same
material.

Any reasons not to go with plaster?

Chris

30 - 40 years ago there was a product sold and given much publicity,
called Acta-Bacta. It was supposed to break down clay soil and I
think that contained gypsum. I tried one sack. It made no
difference!

Pam in Bristol

"Chris J Dixon" wrote
Having just extended a flower bed to incorporate what has been
lawn for 40 years, I am left with some pretty solid clay soil.

Gypsum is recommended as a soil improver, but appears to be sold
in garden centres as a proprietary product costing nearly £5 for
2.5 kg.

http://www.capitalgardens.co.uk/clay...er-p-6321.html

On the other hand, I can pick up a 25 kg bag of multi-finish
plaster for under £5, and AFAIK this is essentially the same
material.

Any reasons not to go with plaster?

Chris, if you can find a Farmers Shop (not a Farm Shop) they may well sell
Agricultural Gypsum in 25kg bags, which is what I bought. Mine was old
stock, a bit lumpy, and I paid £5. each.

--
Regards
Bob Hobden
W.of London. UK

NT wrote:
On Jun 7, 10:34 am, Andy Dingley wrote:
On 7 June, 09:31, NT wrote:

Unused plaster will bind the soil, used lumps wont.
Run it through a cement mixer and a couple of rocks as a ball mill. So
long as you crunch it down enough to go through a sieve, it's fine.
Even just soaking it in an excess of water would be enough (this is
plaster, not cement).

I wouldn't add "rottable garbage" to soil either, it's much better to
rot this down separately. Otherwise you'll be short of nitrogen and
lawns in particular would suffer badly.

So they say, but I've not seen this happen in practice. If you added
wood shavings or plenty of paper I daresay it would.


worms will take care of reducing grass clippings to compost!

But in general, yes. 3 years and then apply compost. You can hurry it
along, but why bother?

Gardening is a long term investment.

NT

"Tim Watts" wrote

I must admit - I don't know if British Gypsum do recycling at the
Mountfield/Robertsbridge plant. Though if they can take crap out the
ground and turn it into plaster (they do all that here) I would have
thought they would have added a preprocessing feed for doing whatever you
need to old PB and sticking the result of it in with the raw materials
from the mine.

British Gypsum make cat litter too, Nature Cat Gold, so that is probably
also gypsum and it's in granules too. Should be available at any good pet
place or could be ordered, but check the price first. Worth ringing BG first
to find out if it is pure gypsum.

--
Regards
Bob Hobden
W.of London. UK

NT wrote:
On Jun 7, 8:57 am, Chris J Dixon wrote:
Having just extended a flower bed to incorporate what has been
lawn for 40 years, I am left with some pretty solid clay soil.

Gypsum is recommended as a soil improver, but appears to be sold
in garden centres as a proprietary product costing nearly 5 for
2.5 kg.

http://www.capitalgardens.co.uk/clay...itioner-p-6321....

On the other hand, I can pick up a 25 kg bag of multi-finish
plaster for under 5, and AFAIK this is essentially the same
material.

Any reasons not to go with plaster?

Chris


Building plaster has other stuff in it besides gypsum, anyone know
what those additives are?


filler mainly. Mica and so on. that's yer carlite bonding anyway.

The finishing plaster is almost pure gypsum IIRC.



NT

Bob Hobden wrote:
"Tim Watts" wrote

I must admit - I don't know if British Gypsum do recycling at the
Mountfield/Robertsbridge plant. Though if they can take crap out the
ground and turn it into plaster (they do all that here) I would have
thought they would have added a preprocessing feed for doing
whatever you need to old PB and sticking the result of it in with
the raw materials from the mine.

British Gypsum make cat litter too, Nature Cat Gold, so that is
probably also gypsum and it's in granules too. Should be available at
any good pet place or could be ordered, but check the price first.
Worth ringing BG first to find out if it is pure gypsum.

No, that's made from bentonite clay, which is the most absorbent, clumpy
dirt the Earth can offer.


Ian

On Jun 7, 1:46*pm, Chris J Dixon wrote:
Ragnar wrote:

"Chris J Dixon" wrote in message
.. .
Having just extended a flower bed to incorporate what has been
lawn for 40 years, I am left with some pretty solid clay soil.

Gypsum is recommended as a soil improver, but appears to be sold
in garden centres as a proprietary product costing nearly 5 for
2.5 kg.

http://www.capitalgardens.co.uk/clay...itioner-p-6321.....

On the other hand, I can pick up a 25 kg bag of multi-finish
plaster for under 5, and AFAIK this is essentially the same
material.

Any reasons not to go with plaster?
I don't really know the answer to your question, but I would warn you not to
use gypsum if you want lime-hating plants such as heathers, rhododendrons
etc

Other sources seem to be of the opinion that one of the benefits
of using gypsum is that it is essentially neutral, and will not
alter pH.

Gypsum is calcium sulphate which is more or less neutral but is
calcium rich which will hurt alpines. Nothing seems to hurt
rosydandelions.

Sand is neutral and acid. Use a mix of sand and gypsum with sawdust or
shedded organic stuff. Grow lupins for a while. Any nitrogen loss will
soon come back.

Sand and clay = loam. I think sand and gypsum = marl.

On 7 June, 14:48, "spamlet" wrote:
"Chris J Dixon" wrote in messagenews:009p061f4aaf3f8kut728pv6q66ataa0fp@4ax .com...





Having just extended a flower bed to incorporate what has been
lawn for 40 years, I am left with some pretty solid clay soil.

Gypsum is recommended as a soil improver, but appears to be sold
in garden centres as a proprietary product costing nearly �5 for
2.5 kg.

http://www.capitalgardens.co.uk/clay...itioner-p-6321....

On the other hand, I can pick up a 25 kg bag of multi-finish
plaster for under �5, and AFAIK this is essentially the same
material.

Any reasons not to go with plaster?

Chris
--
Chris J Dixon �Nottingham UK


Have dancing shoes, will ceilidh.

Interesting how gypsum comes out of nasty thick clay pits, yet we put it
back in as a clay improver?

S- Hide quoted text -

- Show quoted text -

Most gypsum come from scrubbers fitted to coal burning power
stations. The sulphur dioxide converts limestone to calcium
sulphate. The best permanent clay improver is "sharp" sand. The
difficult bit is mixing it thoroughly with the clay. Even a
rotovator is not very good as it only churns up the top layer. It's
taken me three years to get it mixed with hand digging but the results
are good. Compost is the way to go too.
Get yourself a shredder if you have a big hedge. If you know a
landscape gardener, you get get truck loads of shreddings off them for
free. They compost down very quickly if there's lots of leaf. ie
Summer time is the best.