"bruce" wrote in message
...
david taylor wrote:
Do the standard thing-add calcium. Lime for vegetables, chalk if you've
got
growing plants or fresh fertiliser in the ground or gypsum if you need
to
maintain acidity.
2ozs/square yard of lime a little more chalk-I reckon about 4ozs for
gypsum
although I've never used it.
Calcium ions cause edge to edge flocculation in the clay and make it
form a
crumb rather than a slimy plastic structure.
David T

"Nick Maclaren" wrote in message
...

In article ,
bruce writes:
|
| I have an allotment with a very clay soil. Plenty of muck and compost
| helps but I believe that I need to add some coarse grit or sand to
help
| break it up. Horticultural sand is quite expensive so can I use
builders
| sand or is it treated with chemicals that would harm my soil and
| vegetables? Or has anyone got any other suggestions?

Don't use builder's sand! But do use sharp sand from a builder's
merchant. No, it's not treated with chemicals.


Regards,
Nick Maclaren.



That was an excellently rapid response...
I do use lime - should have said. But I don't want to overdo it and make
my soil too alkaline, so I usually reserve it for when I'm planting
brassica. Where do I get gypsum from - I don't recall seeing it anywhere?
I didn't appreciate builders sand and sharp sand were different products
- will a builder's merchant know the difference?

Sharp sand is gritty to the touch, the grains are angular, in my neck of the
woods it is
a light grey colour. Builder's sand is also known as soft sand and is
usually a golden
colour, soft to the touch, staining your fingers yellow, and made up of many
different
sizes of rounded particle, down to clay size. It is good for bricklaying and
mortar.

Andy.