Nick Maclaren wrote:
The main choice is between a hard and soft mortar. The former will
last longer, discourage weeds better, but will let rain through
less well, and will damage the slabs if you ever need to take them
up for any reason.

I used 8 parts of sharp sand to one of cement, laid dry, and it is
a very soft mortar. Look at Cormaic's pages (hunt down the
uk.rec.gardening FAQ by a Web search) for other types.


Regards,
Nick Maclaren.

Thanks, I used a 1:4 dry mix of cement:soft sand in the end. I watered
the gaps first. We'll see what happens, looks OK.

Mark.