"Peter James" wrote in message
.. .
kaz44 wrote:

Pack the holes with
saltpetre and plug the top of the holes with putty and leave it all
winter.

As private individuals, how can we get hold of the saltpetre (potassium
nitrate?) ?

--
M Stewart
Milton Keynes, UK
http://www.megalith.freeserve.co.uk/oddimage.htm